They have a chance to drop addon item but sometimes they drop nothing(I guess thats natural since I killed Worker 2 times and got 1x seed and 1x future orb)
It drops the addon it's wearing, all normal loot of pokemon from which the miniboss originated and perhaps some bonus items (not sure about the last one though)
It drops the addon it's wearing, all normal loot of pokemon from which the miniboss originated and perhaps some bonus items (not sure about the last one though)