I want to add an Atoa Custom Battle System command cut-in.

[kyonides]

There are two easy ways to solve that issue.

First Option

Use $game_party.actors.size instead of $game_party.party_size to get the actual size. (Yeah, I admit the name he has chosen for the method is kind of redundant. )

Second Option

Define party_size like this:

Code:

class Game_Party
  def party_size() @actors.size end
end

Paste it in any script section or just below Wulfo's script.