msem-instigator

As long as you control four or more differently named lands, creatures you control get +1/+1.
As long as you control a land named Far-Off Lands, creatures you control get +1/+1.

({T}: Add {U}.)
Aerie's Pillar enters the battlefield tapped.
Flying
{2}{U}{U}: Aerie's Pillar becomes a creature in addition to its other types until end of turn.

Flying
Whenever Aether Crosser attacks, you may aetherize another target tapped creature you control. (To aetherize, create a token that's a copy of it, then exile that token.)
Crew 1

{T}, Sacrifice Aether Gateway: Create a tapped Plains token, Island token, Swamp token, Mountain token, or Forest token.

If a creature dealt damage by equipped creature this turn would die, exile that card and draw a card instead.
Equip {1}

You control equipped creature.
Equipped creature has hexproof and can't attack or block.
{3}: Attach Aetherite Shackles to target creature. Activate only as a sorcery.

When Aetherite Vein enters the battlefield, scry 1.
{U}, Sacrifice Aetherite Vein: Return target creature to its owner's hand.

Equipped creature gets +1/+0 and has first strike.
{1}{R}: Equipped creature gets +1/+0 until end of turn.
Equip {2}

Equipped creature gets +2/+1.
Equip multicolored creature {1}
Equip {2}

Whenever a land enters the battlefield under your control, untap Ageless Wanderer.
{1}, {T}: Add one mana of any color.

Menace, trample, indestructible
Whenever Aghavaan Unleashed deals combat damage to a player, that player gets that many poison counters.
At the beginning of your end step, sacrifice another creature or transform Aghavaan Unleashed.

{T}: Add {C}.
At the beginning of each end step, if you control five or more Snake creatures, transform Aghavaan's Wound.

{T}, Discard a card: Add {C}.
Whenever you discard one or more cards, you may pay {2}. If you do, draw a card.

Archive X, where X is the number of planeswalkers you control. (As this enters the battlefield, shuffle the top X cards of your main library into a new face up library. Sacrifice this when the archived library is empty.)
Remove a loyalty counter from a planeswalker you control: Draw a card from the archived library.

You may spend mana as though it were mana of any color to cast planeswalker spells.
[–1]: Put a -1/-1 counter on target tapped creature.
[–2]: You gain 2 life for each tapped creature your opponents control.
[–3]: Destroy all creatures that attacked a planeswalker you controlled since your last turn.

{T}: Add {C}.
Tap three differently named untapped Academies you control: Put a +1/+1 counter on target permanent. Activate only as a sorcery.

You have no maximum hand size.
{T}: Add {C}.
{3}, {T}: Create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)

{T}: Add {C}.
{T}, Sacrifice Alchemist's Abode and another permanent: Draw a card. Activate only during your turn.

{T}, Pay 1 life: Add {G} or {U}.
{2}, {T}, Sacrifice Alchemist's Laboratory and another permanent: Draw a card. Activate only during your turn.

{T}, Sacrifice a Treasure, Gold, or permanent named Lotus Petal: Add two mana of any one color.
{T}, Sacrifice a Clue or Omen: Scry 2, then draw a card.
{T}, Sacrifice an Idol: Put two +1/+1 counters on target creature.
{T}, Sacrifice a Food: You gain 6 life.
{T}, Sacrifice a Bullet: Alchemos, Efficiency Engine deals 3 damage to any target.

Equipped creature gets +1/+0 for each Equipment attached to it.
Equip {1}

[+1]: Whenever a creature you control attacks this turn, Aleryn, Dungeon Disabler deals 1 damage to the defending player.
[–1]: Add X mana in any combination of {R} and/or {G}, where X is the number of creatures you control.
[–6]: You get an emblem with “Whenever a player casts a spell, this emblem deals 3 damage to any target.”

When All-Blossom Memorial enters the battlefield, scry 1.
Prismatic — Whenever you cast a multicolored spell, you gain 1 life.
{T}: Add one mana of any color.

({T}: Add {G} or {W}.)
Alpine Meadow enters the battlefield tapped.

Alquyut Mount can't attack or block alone.