Tribal Flames
Sorcery
Domain — Tribal Flames deals X damage to any target, where X is the number of basic land types among lands you control.
"Fire is the universal language." —Jhoira, master artificer
Tony Szczudlo
Rulings
Domain abilities count the number of basic land types among lands you control, not how many lands you control or how many of any type.
(wotc • 2021-06-18)
The basic land types are Plains, Island, Swamp, Mountain, and Forest. Land types other than basic land types (such as Desert) don’t contribute to domain abilities.
(wotc • 2021-06-18)
Rulings
Domain abilities count the number of basic land types among lands you control, not how many lands you control or how many of any type.
(wotc • 2021-06-18)
The basic land types are Plains, Island, Swamp, Mountain, and Forest. Land types other than basic land types (such as Desert) don’t contribute to domain abilities.
(wotc • 2021-06-18)