Apocalypse Hydra enters the battlefield with X +1/+1 counters on it. If X is 5 or more, it enters the battlefield with an additional X +1/+1 counters on it. {1}{R}, Remove a +1/+1 counter from Apocalypse Hydra: It deals 1 damage to any target.

Capricopian enters the battlefield with X +1/+1 counters on it. {2}: Put a +1/+1 counter on Capricopian, then you may reselect which player Capricopian is attacking. Only the player Capricopian is attacking may activate this ability and only during the declare attackers step. (It can't attack its controller.)

{X}{G}{G}{G}: Monstrosity X. (If this creature isn't monstrous, put X +1/+1 counters on it and it becomes monstrous.) As long as Domesticated Hydra is monstrous, it has trample.

Feral Hydra enters the battlefield with X +1/+1 counters on it. {3}: Put a +1/+1 counter on Feral Hydra. Any player may activate this ability.

Vigilance Hydra spells you cast cost {4} less to cast. Whenever a creature you control becomes the target of a spell, Gargos, Vicious Watcher fights up to one target creature you don't control.

When you cast this spell, reveal the top X cards of your library. You may put a nonland permanent card with mana value X or less from among them onto the battlefield. Then shuffle the rest into your library. Genesis Hydra enters the battlefield with X +1/+1 counters on it.

Hungering Hydra enters the battlefield with X +1/+1 counters on it. Hungering Hydra can't be blocked by more than one creature. Whenever Hungering Hydra is dealt damage, put that many +1/+1 counters on it. (It must survive the damage to get the counters.)

{X}{X}{G}: Monstrosity X. (If this creature isn't monstrous, put X +1/+1 counters on it and it becomes monstrous.) When Hydra Broodmaster becomes monstrous, create X X/X green Hydra creature tokens.

Whenever an instant or sorcery spell you control that targets only a single creature deals damage to that creature, Imodane deals that much damage to each opponent.

Trample Whenever a player casts a spell, put a +1/+1 counter on Managorger Hydra.

This spell can't be countered. Haste, protection from blue Mistcutter Hydra enters the battlefield with X +1/+1 counters on it.