So basically there's an item that turns plants trees when an enemy is defeated.
There's an enemy that can cast spells on the player, one of which is a shrink spell, but the player can block it by putting it toward the blue guy by summoning him.
When the blue guy gets hit with that spell, he stops and mocks that enemy, and there's a 1/6 chance for it to mock them relating to an item the player has, and with that tree item mentioned, he tells that enemy 'Be useful and become a tree." So that's how it can tell an enemy to die.
