Card

Priest of Titania

Mana cost {1}{G}

{T}: Add {G} for each Elf on the battlefield.

Part of 82 known combos, 4 of them two-card. 2 official rulings.

Bracket

B1 Exhibition — Not in the same deck as its two-card combo partners: Staff of Domination, Umbral Mantle, Sword of the Paruns, Ringing Strike Mastery
B2 Core — Not in the same deck as its two-card combo partners: Staff of Domination, Umbral Mantle, Sword of the Paruns, Ringing Strike Mastery
B3 Upgraded — Not in the same deck as its early two-card combo partners: Staff of Domination, Umbral Mantle, Sword of the Paruns, Ringing Strike Mastery
B4 Optimized — allowed: No restriction beyond the banned list
B5 cEDH — allowed: No restriction beyond the banned list

Two-card combo with Staff of Domination, Umbral Mantle, Sword of the Paruns, Ringing Strike Mastery (early with Staff of Domination, Umbral Mantle, Sword of the Paruns, Ringing Strike Mastery)

Bracket: Lotus Vault analysis, with Commander Spellbook flags

82 known combos, 4 of them two-card.

Staff of Domination + Priest of Titania
Produces: Infinite card draw, Infinite draw triggers, Infinite lifegain
View on Commander Spellbook
Umbral Mantle + Priest of Titania
Produces: Infinite green mana, Infinitely large creature until end of turn, Infinite untap of creatures you control
View on Commander Spellbook
Ashaya, Soul of the Wild + Scryb Ranger + Priest of Titania
Produces: Infinite creature ETB, Infinite green mana, Infinite landfall triggers
View on Commander Spellbook

2024-06-07 · Wizards of the Coast
Priest of Titania's ability counts all Elves on the battlefield. This includes Priest of Titania itself as well as Elves controlled by other players.
2024-06-07 · Wizards of the Coast
Priest of Titania's ability is a mana ability. It doesn't use the stack and players can't respond to it. Notably, this means other players can't try to remove Elves from the battlefield after you activate this ability but before it resolves.

Rulings: Scryfall · Wizards of the Coast