Deck Idea: Mechanized Springtime in Onu-Koro

March is right around the corner and large parts of the world are entering the beautiful season of spring; Sylphs are abound in Flourishing Hills and Awakening Forests, reviving EARTH monsters and getting their shit kicked in by ghost girls. What better time to look at a new decklist revolving around Onu-Koro, the perhaps even second best Field Spell That Lets You Draw 3 Cards?

Onu-Koro, Village of Earth

Field Spell

You can target up to 5 EARTH monsters in your GY; shuffle them into the Deck, then gain 600 LP for each card shuffled into the Main Deck this way. If your LP are higher than your opponent’s: You can send 1 EARTH monster from your hand or field to the GY, then pay LP in multiples of 1000 (max. 3000); draw 1 card for every 1000 LP paid, then, if your LP are lower than your opponent’s, send that many cards from your hand to the GY. You cannot Normal or Special Summon monsters the turn you activate this effect, except EARTH monsters. You can only use each effect of “Onu-Koro, Village of Earth” once per turn.

Bionicle: Coming of the Toa (v3.21.6)

My main goal with this build was setting up a standard combo line that actually leaves you able to use and resolve this card’s pair of effects to their full potential, by filling the GY with material used to build your board while never summoning any non-EARTH monsters in the process. Previously, the importance of Isolde in the Gouki-based EARTH Warrior shell usually forced you to fail this condition and relegated the village’s ability to just a neat thing you sometimes got to use on later turns, but with the latest banlist, that has become a thing of the past.

For what it’s worth, I still think Gouki is a good fit and meshes well with the general Onu-Koro strategy, but I specifically wanted to experiment with something else here. That “something else” being Vernusylphs, who do a good job of filling both field and GY, coupled with a few Machines that allow us to have some sort of payoff without leaving the confines of our Attribute.

The Deck

https://www.duelingbook.com/deck?id=14840983

.ydk Download

The lineup of monsters in the Main Deck can be divided into three categories:

  • EARTH Matoran, specifically Taipu and Onepu , plus the Ussal to go with the latter. What you’re meant to do is get either of the Matoran on the field by some means and link off into Whenua to search the other, thus providing even more bodies to combo with. Rookie Warrior Lady is also in here as a third potential search target, since she can help refill your hand and even easily sets up Onepu’s Normal Summon effect (sadly it doesn’t do much).
  • Vernusylphs, which are frequently going to be the “by some means” mentioned in the previous paragraph. We play the two that search the rest, and as a one-of search the target the one that dumps an EARTH monster into the GY. Using all three of these already puts up to 4 EARTH monsters in the GY and 3 on the field, and even if we just use one search and the mill, that’s 3 and 2 – basically a complete Onu-Koro setup. The primary target for Awakening Forests is of course going to be the Ussal that will trigger to revive yet another monster (and can then itself be brought back by Onepu), but if you happen to draw that, you can do a cute thing where you discard it for cost with Forests, send something else from the Deck, and then actually do get to bring back that sent monster right away – if it’s Level 4 or lower.
  • EARTH Machines. Just a small package, not the whole deck that kinda does this whole “combo and then draw a bunch” thing way better already. The three names represented here serve three different purposes: Planet Pathfinder is an additional way to get to Onu-Koro, Revolution Synchron is a Tuner so we’re able to access the Naturia Synchros for a reasonable end board, and Regulus is another negate we can add to that if we find him. Which is also possible by means of Discolosseum, which in turn can be provided via Planet Pathfinder, who as a Machine also sets up Regulus’s own Summon (i.e., Planet Pathfinder is an omni negate). The Power Tools are also here for additional Revolution lines, but without Isolde making Equip Spells worth playing they’re not all that useful.

Other than that, we just have a good helping of handtraps that Onu-Koro will hopefully draw for us, as well as generically good EARTH monsters Fenrir and Mudora. Keldo is there in the side deck too, but I only found room for one shuffler, and Mudora was the one to make the cut simply because its Special Summon effect works even without a search target.

The EARTH payoffs in the Extra Deck consist of the aforementioned Naturia Synchros Beast and Barkion, Power Tool Braver Dragon, and Soldier of Chaos. Saryuja is for those times we have a full field but lack the right cards in hand to get anywhere, while Cerberus and Dolmen are mostly just to get stuff linked away in niche scenarios. And Plan B for Bagooska is here too, turns out that fucker is EARTH.

Now you may notice we have also spent some Extra Deck slots on non-EARTH bosses; Baronne and Crystal Wing in the Synchro half, I:P and S:P in the Link half. These are for the times we actually do not manage to get to Onu-Koro, at which point we will have a bunch of material on the field and nothing locking us out of any summons. So might as well put up some good proper household names instead and switch our strategy to the old style where Onu-Koro just shows up as refueling help in the mid to late game.

Sample Video

Takeaways

To me personally, this build honestly feels like a bit of a failure because it doesn’t really seem to get a lot of mileage out of the concept of “combo then draw 3”, despite how solid that sounds on paper. The good news is that there’s some specific reasons for that located within my own designs, which I may be able to fix in future updates. The Onu-Koro cards just trip over themselves in some small ways that didn’t become obvious until I really tried to rely on the Field Spell’s effect that’s supposed to be central to the whole thing.

Onu-Koro, Village of Earth

Field Spell

You can target up to 5 EARTH monsters in your GY; shuffle them into the Deck, then gain 600 LP for each card shuffled into the Main Deck this way. If your LP are higher than your opponent’s: You can send 1 EARTH monster from your hand or field to the GY, then pay LP in multiples of 1000 (max. 3000); draw 1 card for every 1000 LP paid, then, if your LP are lower than your opponent’s, send that many cards from your hand to the GY. You cannot Normal or Special Summon monsters the turn you activate this effect, except EARTH monsters. You can only use each effect of “Onu-Koro, Village of Earth” once per turn.

Bionicle: Coming of the Toa (v3.21.6)

First, there’s Onu-Koro itself. This is a design from an era before Runick Fountain, which means I was super careful with an effect that basically reads “draw 3” and restricted the hell out of it. Only works if you have higher LP (which it does try to provide natively via the shuffle effect), requires sending an EARTH monster from hand or field to GY so you don’t plus as hard, makes you discard as much as you drew if you’re not still ahead on LP after paying the cost, and on top of all that it locks all your Summons into EARTH for the whole turn, including retroactively. Let me tell you, after trying to build this deck, I now fully understand why Vernusylphs went with an effect lock instead – there just aren’t a whole lot of good payoffs in this particular Attribute.

This heavy balancing even bleeds into the shuffling effect, which only gives you back LP for cards you shuffle into the Main Deck, essentially forcing you to choose between valuable Extra Deck recycling and the resource you need to pay for draws. And as a small but nasty detail, it shuffles the cards instead of placing them on the bottom, meaning any deck filtering your combo did to ensure you only draw into, say, handtraps at the end is at least partially undone.

So how would I change this? Well, assuming we stick with the full EARTH Summon lock, I think that can be allowed to carry a lot more weight as a restriction and we can in turn take off some others. Specifically, the requirement to send an EARTH monster for cost always hurt like a bitch in testing, so I’d like to drop that. The discard if you lack sufficient LP is probably fine since it fits the flavor (and we can capitalize on it by making Onu- cards with GY effects), but I’d make it a bit more avoidable by making it easier to gain LP when you return cards to the Deck. The shuffle effect could say “gain 600 LP for each targeted card, then shuffle them into the Deck” or something like that and it would already be much better. That way it would even work properly with Midak too.

Matoran Tender Midak

Effect MonsterLevel 2 | EARTH Warrior | ATK 500 / DEF 500

If you control a “Matoran” monster, except “Matoran Tender Midak”: You can send this card from your hand to the GY; send 1 EARTH monster from your Deck to the GY, and if you do, gain 400 LP. If this card in your GY would be returned to the Deck by a card effect, you can add it to your hand instead. You can only use each effect of “Matoran Tender Midak” once per turn.

Bionicle: Coming of the Toa (v3.21.6)

Speaking of Midak, why was that guy not in the decklist at all? Because, dear reader, the dumbass who wrote his first effect made it basically unusable if you’re not spamming Matoran enough to always have one around. That wasn’t the case in this deck, though, and after wishing for the nth time that I could just search Midak with Whenua and actually use him reliably, I sadly had to cut him.

But yeah, that’s also my solution: Make it so he actually always works when you search him with Whenua, because there aren’t a lot of good search targets for our Turaga anyway. To achieve that, the first line simply has to change to “If you control a “Matoran”, “Toa”, or “Turaga” monster” – perfectly reasonable because they belong together in the lore anyway.

Turaga Whenua

Link Effect MonsterLink-2 [▼ ▶] | EARTH Spellcaster | ATK 1450

2 monsters, including an EARTH Warrior monster
Each time an EARTH monster(s) is sent from your hand or field to the GY, gain 400 LP for each. If this card is Link Summoned: You can pay 1000 LP; add 1 Level 4 or lower EARTH Warrior monster from your Deck to your hand, with a different name from the cards in your GY. You can only use this effect of “Turaga Whenua” once per turn.

Bionicle: Coming of the Toa (v3.21.6)

Whenua himself isn’t safe from my complaints either, though only in a minor way. I’ve mentioned here and there that any numbers I write on cards tend to be guesstimates, and the 1000 LP cost is a good example of that. Only now, after actually playing in a way that made it important to earn it back, have I realized that the correct number was 800 all along: The exact amount you need to break even off a single instance of using two EARTH monsters as material while Whenua watches, and also the amount you would gain from using a Midak he searched. Fool that I was to disregard the ancient mantra of “pay 8, feel great”.

Matoran Racer Onepu

Effect MonsterLevel 2 | EARTH Warrior | ATK 700 / DEF 500

When this card is Normal Summoned: You can target 1 of your banished EARTH monsters; place it on the bottom of the Deck, then you can reveal any number of “Matoran” monsters in your hand, and if you do, gain 500 LP for each. During your Main Phase: You can Special Summon 1 Level 4 or lower Beast “Rahi” monster from your hand or GY, but banish it when it leaves the field. You can only use each effect of “Matoran Racer Onepu” once per turn.

Bionicle: Challenge of the Rahi (v3.20.4)

Onepu has served us well as an Ussal fetcher, but his other effect has really proven to be damn useless – especially in a deck that, once again, isn’t filled to the brim with Matoran. I think I wanted to hold back on this one because the main purpose is just to get a spent Ussal back into rotation, but surely you can expect more from a Normal Summon. My initial idea of having it draw à la Chaos Space was rejected (by me) because a) Onu-Koro is supposed to be the draw provider, everything else just makes “money” (LP) to pay for it, and b) “but Chaos Space is so strong, that would be broken”.

Regarding a), I now realize that a second source of draws probably wouldn’t hurt at all, as the old saying about putting all your eggs in one basket could have told us all along. And b) was always stupid when you consider that Chaos Space does its thing from the GY rather than at the cost of your Normal Summon and supports Attributes that are significantly better equipped than EARTH.

The current LP gain does have the funny flavor of “Onepu brags to the Matoran in hand and gets rewarded”, but we can actually retain that if we just let you do the same thing after drawing a card – or even just reveal the drawn card itself.

Side note to fully tie the loop here, notice how Onepu makes the Rahi he summons get banished when it leaves the field? That also means it can’t be used to pay the monster cost for Onu-Koro, so even if we weren’t getting rid of that cost entirely it would at least have to change to say “Tribute” or something like that. Nothing feels worse than the cards that are meant to go together in a deck locking themselves out of actually working with each other.


For now, I’ve compiled these notes on the secret Pending Changes page, and will be trying to work them in over the course of upcoming releases.

Theme Guide: Onu-Koro (BCOT)

Onu-Koro, Village of Earth

Field Spell

You can target up to 5 EARTH monsters in your GY; shuffle them into the Deck, then gain 600 LP for each card shuffled into the Main Deck this way. If your LP are higher than your opponent’s: You can send 1 EARTH monster from your hand or field to the GY, then pay LP in multiples of 1000 (max. 3000); draw 1 card for every 1000 LP paid, then, if your LP are lower than your opponent’s, send that many cards from your hand to the GY. You cannot Normal or Special Summon monsters the turn you activate this effect, except EARTH monsters. You can only use each effect of “Onu-Koro, Village of Earth” once per turn.

Bionicle: Coming of the Toa (v3.21.6)

In the underground caverns of Onu-Koro, hard work is rewarded with great wealth, at least according to the Principle of Prosperity. For the effects of the Field Spell, I interpreted “hard work” as “putting monsters in the GY”, which is usually a pretty decent indication you’re doing things, and “wealth” as the resources of both LP and cards. So the first effect trades the proof of your work, the monsters in the GY, for wealth in the form of LP, and the second directly trades that amassed wealth for cards.

There are several extra balancing factors to the draw effect, given that it can potentially draw up to 3. First, it only works when you have higher LP, so you have to do some healing and/or damage before using it. Second, you need to send an EARTH monster from your hand or field to the GY, mainly to downgrade the level of advantage you get and to make the effect a bit more conditional, but also as setup for LP regeneration. Third, if you pay so much that you are now behind in LP, you lose an equal number of cards to what you drew, which technically works out to a -1 but is still fairly good since you can freely put anything from your hand into the GY. Fourth, it locks you into only summoning EARTH monsters for the whole turn, just to be extra sure it doesn’t get randomly abused. A proper Onu-Koro deck is mostly okay with this restriction anyway.

It follows that, as an Onu-Koro player, you want to establish a stable loop of putting EARTH monsters in the GY while building your board, shuffling them back to gain LP, and potentially drawing additional cards to further strengthen your position. Now we’ll take a look at how other cards contribute towards that goal.

Turaga Whenua

Link Effect MonsterLink-2 [▼ ▶] | EARTH Spellcaster | ATK 1450

2 monsters, including an EARTH Warrior monster
Each time an EARTH monster(s) is sent from your hand or field to the GY, gain 400 LP for each. If this card is Link Summoned: You can pay 1000 LP; add 1 Level 4 or lower EARTH Warrior monster from your Deck to your hand, with a different name from the cards in your GY. You can only use this effect of “Turaga Whenua” once per turn.

Bionicle: Coming of the Toa (v3.21.6)

Noble Kanohi Ruru

Equip Spell

If another “Kanohi” card becomes equipped to the equipped monster, destroy this card. You can only use each of the following effects of “Noble Kanohi Ruru” once per turn.
●While this card is equipped to a “Turaga”, “Toa”, or “Makuta” monster: You can target 1 Set card your opponent controls; reveal it. If it is a Spell/Trap, inflict 500 damage to your opponent. If it is a monster with less ATK than the equipped monster, inflict damage to your opponent equal to the difference.
●If this card is in your GY: You can Tribute 1 monster, then target 1 “Turaga Whenua” in your GY; Special Summon it and equip it with this card.

Bionicle: Coming of the Toa (v3.21.6)

Whenua essentially acts as an overseer of the “work” you perform, providing small rewards in real time for every EARTH monster you put into the GY. On summon, he also helps you solve your current problems by learning from the mistakes of the past, or in non-lore terms, searches a low-level EARTH Warrior that isn’t in your GY yet. Of course, putting stuff back with Onu-Koro expands your search range here.

The Kanohi Ruru, Mask of Night Vision, doesn’t really have a main focus that synergizes with the Onu-Koro deck much – it just reveals Set cards, because that’s the mechanic that historically fits night vision best (for the record, hand reveals would be mind reading). It does also inflict some damage as a bonus, which could at least help achieve the necessary LP difference to use Onu-Koro to its full potential.

The search effect on Whenua is of course meant to fetch Onu-Matoran, and for that we have a few options.

C.C. Matoran Taipu

Effect MonsterLevel 2 | EARTH Warrior | ATK 1000 / DEF 500

You can Special Summon this card (from your hand), but you cannot declare an attack for the rest of this turn, except with “C.C. Matoran” monsters. You can only Special Summon “C.C. Matoran Taipu” once per turn this way. If this card is sent from the field to the GY: You can target 1 monster you control with less than 2000 ATK; it gains 1000 ATK/DEF until the end of the next turn.

Bionicle: Coming of the Toa (v3.21.6)

Matoran Tender Midak

Effect MonsterLevel 2 | EARTH Warrior | ATK 500 / DEF 500

If you control a “Matoran” monster, except “Matoran Tender Midak”: You can send this card from your hand to the GY; send 1 EARTH monster from your Deck to the GY, and if you do, gain 400 LP. If this card in your GY would be returned to the Deck by a card effect, you can add it to your hand instead. You can only use each effect of “Matoran Tender Midak” once per turn.

Bionicle: Coming of the Toa (v3.21.6)

Matoran Racer Onepu

Effect MonsterLevel 2 | EARTH Warrior | ATK 700 / DEF 500

When this card is Normal Summoned: You can target 1 of your banished EARTH monsters; place it on the bottom of the Deck, then you can reveal any number of “Matoran” monsters in your hand, and if you do, gain 500 LP for each. During your Main Phase: You can Special Summon 1 Level 4 or lower Beast “Rahi” monster from your hand or GY, but banish it when it leaves the field. You can only use each effect of “Matoran Racer Onepu” once per turn.

Bionicle: Challenge of the Rahi (v3.20.4)

Taipu is most importantly a free Special Summon from the hand, assuming it is either turn 1 or Main Phase 2 – otherwise there’s an attack restriction that can trip you up sometimes, fitting for a somewhat clumsy Matoran who is always eager to help. Aside from these attributes, Taipu is also notable for his unusual physical strength, reflected in his unusually high ATK stat which matches the stat boost he gives another small monster when sent from field to GY. You can also use that for chain blocking.

Midak, the eccentric Onu-Matoran who likes sunlight and spends his time in a hut full of Ussals on the surface, is the first half of a little engine that takes advantage of the deck’s built in resource cycling. His role is sending an EARTH monster from your Deck to the GY (yes, can be anything, hence the restriction to needing a Matoran on the field) for setup and some immediate LP gain, and later returning directly to your hand when he would be shuffled back by Onu-Koro, because the Deck is too dark for his tastes.

The second half of the combo is Onepu, the proud champion of the Ussal races. Having such a defining relationship with the crab Rahi, he actually interacts directly with it by Summoning it (or any other low-level Beast Rahi) from the GY. On Normal Summon, he can put a banished EARTH monster (such as an Ussal used in a previous iteration) back into your Deck and be rewarded with LP gain proportional to the size of his audience in your hand. So what exactly is the combo I’m talking about here? Well, the one missing key point is that the Ussal, a Level 4 EARTH Beast member of the Rahi archetype, can bring back another Level 4 or lower EARTH Beast monster from the GY when sent there.

Ussal, Crab Rahi

Pendulum Effect MonsterLevel 3 | Scale 2/2 | EARTH Beast | ATK 1000 / DEF 1000

Pendulum Scale = 2
[ Pendulum Effect ]
Once per turn: You can reduce the Pendulum Scale of the card in your other Pendulum Zone by 1 until the End Phase; this turn, while this card is in your Pendulum Zone, you can also Pendulum Summon “Rahi” Pendulum Monsters from your GY, but monsters Summoned this way are destroyed during the End Phase.
—————————————-
[ Monster Effect ]
If this card is sent to the GY: You can Special Summon 1 Level 4 or lower EARTH monster from your GY, except this card. If this card is banished: You can Special Summon 1 Level 3 or lower “Rahi” monster from your GY. You can only use 1 “Ussal, Crab Rahi” effect per turn, and only once that turn.

Bionicle: Challenge of the Rahi (v3.15.5)

What you do is this: Put Onepu on the field, activate Midak in your hand to send himself and an Ussal from the Deck to the GY, the Ussal triggers to bring back Midak, and with Onepu bringing back the Ussal you now have 3 monsters on the field. Do whatever combos you so desire from here, and once you’re done use Onu-Koro to shuffle back a bunch of EARTH monsters, including Midak who will instead come to your hand. Then on a subsequent turn you just need to find Onepu again, and due to him putting back the banished Ussal on Normal Summon everything is ready to go for another round.

A potential hole in our whole strategy of continuously shuffling monsters from the GY back to heal and draw is that we will eventually run out of Spells and Traps, as those are not recycled. It may not matter a lot of the time, but still, to our rescue comes the wise Toa of Earth.

Toa Mata Onua

Effect MonsterLevel 6 | EARTH Warrior | ATK 2100 / DEF 2100

To Tribute Summon this card face-up, you can Tribute an EARTH or “Toa Mata” monster in your hand, except “Toa Mata Onua”, instead of a monster you control. Once per turn, if a monster(s) is sent from the hand or Deck to the GY: You can target 1 card in either GY; place it on the top or bottom of the Deck, and if it was a monster whose original ATK in the GY was lower than this card’s current ATK, gain LP equal to the difference.

Bionicle: Coming of the Toa (v3.21.6)

Great Kanohi Pakari

Equip Spell

If another “Kanohi” card becomes equipped to the equipped monster, destroy this card. If the equipped monster is a “Toa” or “Makuta” monster, it gains 1000 ATK, also if it attacks a Defense Position monster, inflict piercing battle damage. If this card is sent to the GY: You can banish 1 monster from your GY; add 1 “Toa Mata Onua” from your Deck to your hand. You can only use this effect of “Great Kanohi Pakari” once per turn.

Bionicle: Coming of the Toa (v3.21.6)

Indeed, Onua gives us the ability to return any card from the GY to the Deck, assuming the trigger of a monster being sent from hand or Deck to GY applies. And beyond simple recycling, he comes with the benefits of working on both GYs, being able to place the card either on top or bottom of the Deck, and healing you if you return a monster with lower ATK than him. This means he can put your own Spells/Traps just a draw away, place something dead on top of the opponent’s Deck, take something they just sent to the GY away before it can be used, or simply be used for LP regeneration to enable Onu-Koro.

The Kanohi Pakari, Great Mask of Strength, also plays into these LP games. The bonus ATK on Onua makes it so you stand to gain more LP from his effect, and a high-ATK piercer is a pretty reliable way to damage your opponent and help establish the desired LP difference.

Sample Deck

https://www.duelingbook.com/deck?id=6583242

Our goal is to do “work” – putting monsters from hand or field into the GY – as quickly as possible to get our LP and card advantage engine fueled, so this is basically a Link spam deck. In addition to our core engine of Taipu/Onepu/Midak/Ussal, the stars of this deck are the Goukis, which allow us to just keep throwing monsters onto the field while also refilling the hand with their own floating effects, supplementing the draws we get from Onu-Koro later in the game. Visiting the village are the Chronicler Takua and Po-Koro‘s Hafu, which together form yet another way to get out a total of up to three monsters off one card (though banishing the one Hafu summons is a little detrimental to our resource loop).

The ultimate payoffs going first are usually some combination of Knightmare Gryphon, Apollousa, and Tri-Gate Wizard, while going second the big power play is obviously Accesscode. Grandsoil is both a main deck boss and a combo piece that is very easy to use in this strategy, since you can easily control the number of EARTH monsters in your GY.

Best of Test

Best of Test: Onu-Koro

Conclusion

The greatest strength of Onu-Koro decks is the ability to replenish resources, both cards and LP, over and over again. Even if you can’t kill your opponent quickly, you can probably survive long enough to outlast them if things go reasonably well, though most of the time there isn’t a need to drag things out too much.