mtg.wtf

When Arboreal Alliance enters the battlefield, create an X/X green Treefolk creature token.
Whenever you attack with one or more Elves, populate.

Reach
When Arboreal Grazer enters the battlefield, you may put a land card from your hand onto the battlefield tapped.

Prototype {1}{U}{U} — 2/1
When Arcane Proxy enters the battlefield, if you cast it, exile target instant or sorcery card with mana value less than or equal to Arcane Proxy's power from your graveyard. Copy that card. You may cast the copy without paying its mana cost.

Before you shuffle your deck to start the game, you may reveal this card from your deck and exile an instant or sorcery card you drafted that isn't in your deck.
When Arcane Savant enters the battlefield, copy a card you exiled with cards named Arcane Savant. You may cast the copy without paying its mana cost.

Flying
When Arcanist's Owl enters the battlefield, look at the top four cards of your library. You may reveal an artifact or enchantment card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

First strike
When Arcbound Shikari enters the battlefield, put a +1/+1 counter on each other artifact creature you control.
Modular 2

When Archaeomancer enters the battlefield, return target instant or sorcery card from your graveyard to your hand.

When Archaeomancer's Map enters the battlefield, search your library for up to two basic Plains cards, reveal them, put them into your hand, then shuffle.
Whenever a land enters the battlefield under an opponent's control, if that player controls more lands than you, you may put a land card from your hand onto the battlefield.

When Archaeomender enters the battlefield, return target artifact card from your graveyard to your hand.

Flash
Flying, vigilance
When Archangel Avacyn enters the battlefield, creatures you control gain indestructible until end of turn.
When a non-Angel creature you control dies, transform Archangel Avacyn at the beginning of the next upkeep.

Kicker {B} and/or {R}
Flying, lifelink
When Archangel of Wrath enters the battlefield, if it was kicked, it deals 2 damage to any target.
When Archangel of Wrath enters the battlefield, if it was kicked twice, it deals 2 damage to any target.

Flying
When Archfiend of Sorrows enters the battlefield, creatures your opponents control get -2/-2 until end of turn.
Unearth {3}{B}{B}

Lifelink
When Archfiend's Vessel enters the battlefield, if it entered from your graveyard or you cast it from your graveyard, exile it. If you do, create a 5/5 black Demon creature token with flying.

When Architects of Will enters the battlefield, look at the top three cards of target player's library, then put them back in any order.
Cycling {U/B}

Flying
Ward {2}
When Archive Dragon enters the battlefield, scry 2.

Flying
When Archon of Coronation enters the battlefield, you become the monarch.
As long as you're the monarch, damage doesn't cause you to lose life.

Flying
When Archway Angel enters the battlefield, you gain 2 life for each Gate you control.

Archway Commons enters the battlefield tapped.
When Archway Commons enters the battlefield, sacrifice it unless you pay {1}.
{T}: Add one mana of any color.

Cumulative upkeep {2}
When Arctic Wolves enters the battlefield, draw a card.

When Arcum's Astrolabe enters the battlefield, draw a card.
{1}, {T}: Add one mana of any color.

When Ardent Electromancer enters the battlefield, add {R} for each creature in your party.

When Ardent Elementalist enters the battlefield, return target instant or sorcery card from your graveyard to your hand.

Legendary creatures don't untap during their controllers' untap steps.
When Arena of the Ancients enters the battlefield, tap all legendary creatures.

Enlist
When Argivian Cavalier enters the battlefield, create a 1/1 white Soldier creature token.

When Argothian Opportunist enters the battlefield, create a tapped Powerstone token.