One Turn Faster Than Scavenger

I've been working on Trove Combo for the last few days, and this is my current build. I'm not sure exactly how good the deck is, but it is definitely playable. The deck title comes from the comparison with Scavenger - your goldfish is a full turn faster, meaning that you have quite reliable T5 kills if opponent has absolutely no interaction. It is easier to interact with this deck than with Scavenger, but also this deck is more resilient against interaction when it happens.

I've tried a few different combo setups with Trove, but I settled on one that is very similar to TRXRT's older deck Praxis Trove Combo. The plan is as follows:

T0: mull for a merchant.

T1, T2: play crests to try to find whatever you are missing in order to combo (including 3rd power). If you need to, you can play a plunder unit here to make sure you can play a merchant on T3, but usually you want to save units to use with trove or pitch to merchants.

T3: play a merchant and get Praxis Trove. If you have multiple merchants, usually you want to keep a praxis smuggler in hand if possible to get Unearth if the opponent kills your trove.

T4: play Praxis Trove. If you have an undepleted power and a 1-drop, you can play that this turn as well, but it isn't necessary (you can often win easily without ever playing a 4th power).

T5: If your T3 merchant is still alive, you can usually win this turn. The win is as follows:

1-drop (note that Shepherd or Kato can be used for this) -> Crack for WWH

2-drop -> Reweave -> turn your merchant into a new merchant, getting Scattershot from market and triggering Trove again

reweaved merchant -> DoD sacrificing something for 6 power

Scattershot -> Harmony giving a bunch more power

WWH -> EoH, and now you are done with Trove and just win with scattershot + WWH + EoH.

There are a few different ways of doing a ton of damage from here - exactly how much damage you can do depends on how many units you have in play (fewer is better), but you can generally do 40-50 damage. There are two types of kills that are worth knowing:

Firebrand Kill: Your first EoH targets WWH, and now you have three WWH triggers. Your first WWH trigger is Reweave, turning one of your units into a Firebrand (any of them can be safely sacrificed aside from the Scattershot and the second/third WWH (which are about to infiltrate)), and your second WWH trigger is also Reweave (from now on sacrificing anything other than Scattershot), getting another Firebrand. Your third WWH trigger is EoH on WWH (giving 2 new triggers). From then on, you alternate between DoD sacrificing a unit (to clear board space) and EoH on WWH. You continue this as long as possible - note that even at the very end when your board is totally full and you are down to only one WWH trigger, you should get EoH for more Firebrand damage, but the opponent will probably be dead before then. You can also optionally replace the first DoD with another Reweave for Firebrand if you'd like.

Scattershot Kill: Your first EoH targets Scattershot. Then your first WWH trigger is EoH on WWH, and after that you alternate between DoD and EoH as before. This kill does a bit less damage, but still usually plenty and works even if Firebrand got seeded or something happened to Reweave.

T6+: If your merchant was killed before T5, don't be alarmed - you can still combo off fine, you will just need to draw a second merchant (and usually not get to kill until T6). You can proceed as before, and indeed still play your 1-drop + 2-drop on T5, but the Reweave won't let you fetch a second merchant to kill on T5. Fetch Cartographer instead if you are still looking for the second merchant, or otherwise fetch Kato or Shepherd to have an additional unit out. Then when you have the merchant you can just play it from hand and combo kill as described above. The crests, cylixes, plunderers, Cartographer all do a pretty good job of digging for the second merchant if you didn't already have it from the start.

Summary: the turn 5 goldfish requires a turn 3 merchant, PP influence (for WWH), and a 1-drop and 2-drop by turn 5 (and Shepherd/Kato can be used either as your 1 or as your 2), so these are the things that you should be looking for with crests. If the merchant dies, all you need is a second one, and you don't need to wait for the second one before playing your 1/2.

The opponent can of course interact with your combo in ways other than just killing your merchant. It is worth noting some of your ways of winning through interaction:

fast removal on Scattershot: You should have spare power by this point in the combo for Savage Denial or Unseal if you happened to draw one.

Backlash or similar negate effects: Savage Denial or Unseal will work here too, if you have the spare power at the point in the Trove chain where they try to stop you. You can also sometimes just continue comboing on the following turn - for example, if they negate Crack or Reweave then waiting a turn and playing an additional merchant will do it.

units with annoying text (Katra, Tocas, Aniyah, etc): Huntress can sometimes kill these, or you can use your DoD while comboing to do 4 to it (reweave can get skycrag smuggler) and wait a turn before continuing to combo, or you can market for Equivocate. Firebrand can also sometimes contribute towards killing these.

relic removal: You only have 4 smugglers that can get it, but this is what the market Unearth is for.

This isn't a comprehensive list of things that can go wrong, and some pieces of hate will be harder to win through (e.g. Decree or RoF hitting Trove or WWH is going to be hard, or Milos hitting you is an issue with only one Crack). Sometimes you can manually combo with Scattershot/WWH/EoH enough to push through a win, but you should expect to lose some games because the opponent just had a type of interaction that you couldn't beat.

I'm definitely not fully confident in all the choices made in this build - there are two flex market slots (Unearth/Equivocate), six flex maindeck interaction slots (Savage Denials/Unseals), and then the precise number/choice of 1s/2s/3s is definitely not set in stone (you could even add a 4th color for more merchants that can fetch Trove/Scattershot). Some of these choices will be meta-dependent, e.g. you should play more Cracks and possibly some From Elements if you are concerned about Milos. This current build is focusing more on having a smooth powerbase (with evangels and plunderers) and having a solid number of counters to fast removal.