msem-instigator

Equipped creature gets +1/+3.
{0}: Until end of turn, Ancestor's Bulwark becomes a 1/3 Spirit artifact creature with flying. Activate this ability only if it isn't attached.
Equip {3}

When Ancestor's Skull enters, target creature gets +1/+0 and gains menace until end of turn.
{2}, Sacrifice Ancestor's Skull: Target creature gets +2/+0 and gains menace until end of turn.

({T}: Add {G}.)
As Ancestral Glade enters, you may pay 1 life. If you don't, Ancestral Glade enters tapped.
Basic lands you control have “{T}: Add {G}.”

{T}: Add one mana of any color.
{4}, {T}, Sacrifice Ancestral Tapestry: Search your library for a legendary card, reveal it, put it into your hand, then shuffle.

Flash
When Ancestral Warlord enters, it deals 1 damage to each blocking creature.

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

{3}, {T}: Ancient Artillery deals 1 damage to target creature or planeswalker and 1 damage to that permanent's controller.

Ancient Cairns enters tapped.
As Ancient Cairns enters, choose a color other than red.
{T}: Add {R} or one mana of the chosen color.

Whenever Ancient Durumderm attacks, you may return another creature you control to its owner's hand. If you do, create a Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)

Target creature you control gets +3/+3 until end of turn. Then if that creature has power 10 or greater, each other creature you control gets +3/+3 until end of turn.

Prevent all combat damage that Ancient Guardian would deal to or be dealt by creatures with no counters on them.

Puzzlebox (Begin the game with this and another card you own from outside the game in the command zone, locked. That card is face down until you unlock this.)
{6}: Unlock Ancient Maze. If the revealed card is green, put it into your hand. Otherwise, put it on top of your library.

{T}: Add {C}.
{3}, Discard Ancient Ossuary: Search your library for a land card, reveal it, put it into your hand, then shuffle.

Trample
When Ancient Pillan enters, it fights up to one target creature an opponent controls.

Equipped creature has “Whenever this creature attacks or blocks, choose a creature card in your graveyard. This creature gets +X/+Y until end of turn, where X is that card's power and Y is its toughness.”
Equip {2}

When Ancient Tablet enters, scry 2.
{2}, Sacrifice Ancient Tablet: You may shuffle any number of target cards from your graveyard into your library. Draw a card.

Ward {3}

Flying
When Ancient of Reflections enters, create a token that's a copy of target creature you control not named Ancient of Reflections, except it's 1/1 and has haste. Sacrifice it at end of turn.

When Ancient of the Glade enters, put a +1/+1 counter on each other creature you control.
{2}, Remove a +1/+1 counter from a creature you control: That creature gains indestructible until end of turn.

Defender
Andazir Elite can attack as though it didn't have defender as long as it's equipped.

At the beginning of each end step, if you drew and/or discarded six or more cards this turn, return Anemothrys, Reefcrown from your graveyard to the battlefield.
Cycling {R}{G} ({R}{G}, Discard this card: Draw a card.)

Equipped creature gets +1/+1.
As long as equipped creature is multicolored, it gets an additional +1/+1.
Equip {1}

Reach
Erratic (When this creature dies, reveal the top four cards of your library. Put a creature card that costs less than this revealed this way onto the battlefield and the rest on the bottom of your library in any order.)
When Angelbane Spider enters, destroy target creature with flying.