Rock Hydra (Retro) [30th Anniversary Edition] Legendary Enchantment Creature lands you control have “{T}:

lands you control have “{T}: Add one mana of any color

"Feldon's latest discovery appears to draw upon the same 'memories of the land' my wife studied

Sacrifice two other artifacts and/or creatures: Put an indestructible counter on Mondrak

you may cast that card and you may spend mana as though it were mana of any color to cast that spell

I'm a man of my word

Rock Hydra (Retro) [30th Anniversary Edition] Legendary Enchantment Creature lands you control have “{T}:Set: 30th Anniversary 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.