Cactus Preserve
Land — Desert
Oracle Text
This land enters tapped.
{T}: Add one mana of any type that a land you control could produce.
{3}: Until end of turn, this land becomes an X/X green Plant creature with reach, where X is the greatest mana value among your commanders. It's still a land.
Watch Out
Mana abilities don't use the stackRules Note
If this card's activated ability produces mana and doesn't target, it's a mana ability. Mana abilities resolve immediately without using the stack — opponents can't respond to them. However, abilities that target (even if they produce mana) aren't mana abilities.