Cheapest priced copy (Dominaria United): $0.35 at Card Kingdom, near mint, their price list as of .
Yavimaya Sojourner 
Creature — Treefolk · 4/6 · Common · Dominaria United · #191
Domain — This spell costs {1} less to cast for each basic land type among lands you control.
Legal inCommanderPioneerModernLegacyVintagePauper
Not legal inBrawlStandard
1 printing · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Dominaria United | 191 | Common | $0.35 | $0.49 |
4 rulings from Wizards of the Coast
- 9 September 2022The 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.
- 9 September 2022Yavimaya Sojourner’s first ability can’t reduce the {G} in its cost.
- 9 September 2022To determine the total cost of a spell, start with the mana cost or alternative cost you’re paying, add any cost increases, then apply any cost reductions (such as that of Yavimaya Sojourner). The mana value of the spell is determined by only its mana cost, no matter what the total cost to cast that spell was.
- 9 September 2022Domain abilities count the number of basic land types among lands you control, not how many lands you control or how many of any type.