Ordered Migration
Sorcery
Domain — Create a 1/1 blue Bird creature token with flying for each basic land type among lands you control.
"Birds reach all parts of the world," said Barrin. "They will make excellent scouts."
Heather Hudson
Invasion (INV)
• #258Rulings
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)