Right now sucks so badly, what the matter in having 3 or more clones if any enemy will target Killjoy and kill him like paper and clones PLOP! The enemies keep ignoring the clones and focus on Killjoy, they never kill the clones, they just kill JOY, the idea on paper is good, you must kill the clones to reach the master but the game is not working like that.
1. Make Killjoy untargetable until all the clones are destroyed.
2. Make clones remain despite killjoy dies (he will surely do)