Rock Hydra [Revised Edition] Human Druid Ally Put all creature cards of

Put all creature cards of the chosen type revealed this way into your hand and the rest on the bottom of your library in any order

but I can assure you

Prevent X of that damage

Exile the rest

Enchanted creature has "{T}: This creature deals X damage to target attacking or blocking creature

Rock Hydra [Revised Edition] Human Druid Ally Put all creature cards ofSet: Revised Edition Type: Creature Hydra Rarity: Rare Cost: {X}{R}{R} Rock Hydra enters the battlefield with X +1 +1 counters on it. For each 1 damage that would be dealt to Rock Hydra, if it has a +1 +1 counter on it, remove a +1 +1 counter from it and prevent that 1 damage. {R}: Prevent the next 1 damage that would be dealt to Rock Hydra this turn. {R}{R}{R}: Put a +1 +1 counter on Rock Hydra. Activate only during your upkeep.