@Lord Santa Nice post, Love the Hydra especially.
Could you explain the man-beast capabilities, such as how string is it, how much damage it can take, and other such information, that would be great.
It's something like this:
The man-beast is something Isaac made with quite a few things spliced into them. He calls them the 'hunters' because they can teleport and they have low-level electrical abilities used to stun people. He took a teleporter's abilities as well as the cells of a guy who could discharge electricity and spliced it with some beefy guys. He added some enhanced strength and stuff to the mix and there you go.
As a result, the hunters are quite tough, fast, able to teleport and have really sharp claws as well as enhanced strength and some regeneration. Certain hunters have different ways of teleporting, but that's something I'll keep to myself for now. At any rate, they're mindless but cunning, and Isaac has a lot of control over them when he wants to.
Their stubborness is increased by the fact that they mindlessly obey Isaac's every command and are basically zombies. This makes them more tenacious than tough, but yeah. Isaac can call them back at any time, though that part depends on his reflexes more than anything, and if you kill them fast enough he can't call them back.
Also, their hearts are shifted downwards by a little which was kind of like a side-effect. No one except for Isaac would know that unless someone tries to rip their hearts out and finds a fistful of lung instead. If you need any more details, you can PM me or something.