>>35491061Your damage is actually way too much. I did a rudimentary calc to see how good the effect of Compounder would be, and it turned out monstrous.
For this I'm going to assume that a 5-hit Bullet Seed is the equivalent of a 125 BP Grass move, although the actual numbers are a little different (as seen by moves 1 and 2).
Move 3 is what I imagine the damage of a 25, 28, 31 sequence to be like. Damage is actually fantastic here as Breloom has no investment in Attack aside from IVs and lacks Technician, and can reliably deal 1/3 of a max HP/Def Toxapex's health given 5 hits.
Move 4 is where things get crazy. Using the 25, 53, 84 sequence an uninvested Breloom can kill Toxapex with 5 hits. Note again that vanilla Bullet Seed is a little stronger than the 125 BP move scale I made. I don't know for certain how the actual Compounder boosted move would scale up (or even if it will scale up) but I'm guessing the number would turn out larger.
I realize I may have used some extremities (5 hits doesn't proc every time), but I think my point still stands that Compounder makes a move too strong. Considering that you mentioned it possibly being a legendary exclusive, it may be even stronger depending on the Pokemon's BST and movepool.
I get it's in the ability name and all, but even in real life situations compounding at a 10% rate leads to large figures in a few periods.
If you didn't understand any of that, just imagine the potential to be hit by a 25 BP move, then a 53 BP move, then 84, 118, and ending with 125.
All in the same turn.
tl;dr its too stronk