Super op, compare unupped to minor phoenix, dont even get me started about upped.
The uppeds ability works like guard without the delay I guess (and causes all Hydras to pick the same target, Hydra boss not included)?
If you want Hydra to multiply on death in a way that allows a chain reaction, you have to increase cost to at least 5
. it synergizes with immolation, dry spell, adrenaline, bloodsucker, gravity pull. Upped definitely needs its passives power reduced unless you want it to cost like 15
. I dont get the theme behind turning other creatures into Hydras, i would limit this ability to their own death.
I would change its effect to being identical to unupped, while giving it slightly better stats and the active ability for a minor cost increase.