A free program for Android, by GriselTRC.
This app features a collection of different mutants you can add to your Minecraft.
The first thing you need to know about these mutants is that they are all extremely powerful. You might not be able to kill several of them in a single shot, as their powers could be too much for you. But that is a very good thing about this mod. It should bring a lot of challenge to your gameplay, so you are going to be required to think carefully about your strategies or tactics.
The bosses have devastatingly potent powers as well as special abilities – which can intensify the challenge for you.