Spend only mana produced by basic lands to cast this spell.
"An ancient, powerful force has overtaken the valley. I sympathize for its former inhabitants, but I rejoice for the land itself."
—Olanti, Muraganda druid
An effect that allows you to spend mana as though it were mana of any type to cast Imperiosaur won't allow you to spend mana from a source other than a basic land to cast it.
19-03-2021
wotc
If a triggered mana ability produces mana when a basic land is tapped for mana, that additional mana is produced by the source of the triggered mana ability, not by that basic land.
19-03-2021
wotc
If a basic land gains a mana ability, mana produced with that ability can be spent to cast Imperiosaur.
Random a card of Magic: The Gathering (MTG), but you can also roll the D20 dice, random a Planeswalker, have fun with the random rules and more.
Lars Grant-West2021-03-19
