I don't really see how that'll work, considering the boss will be tiny (I mean the size of a Pikmin? C'mon). I mean how are your Pikmin going to swarm it? Unless you throw a Pikmin at it or something and it takes a chunk off it's damage. But yeah, I like the idea of two separate armies fighting each other...Although I dearly hope there's some way to make more Pikmin as this fight goes on, considering that this whole fight sounds like it's more dependent on luck since you're fighting another army...Just like Pikmin 2 multiplayer (Well, that's what I'm comparing it to).
^This. You have to take in account that the smaler an enemy is, the less feasible it is you could swarm a crap ton of Pikmin on it. Either A) It has low health to begin with, so few Pikmin attacking it makes sense, B) It has high health and it's a slow, tedious battle, or C) Throwing Pikmin on it takes away a chunk of health, like a Breadbug.
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