msem-instigator

Enchant creature
When Mantle of the Returned enters, return target creature card from your graveyard to the battlefield. It's a Zombie in addition to its other types.
Enchanted creature gets +1/+1 for each Zombie you control.

[+2]: Look at the top card of your library. If it's a permanent card with mana value less than the number of lands you control, you may put it onto the battlefield.
[–1]: Sacrifice a land. If you do, draw three cards.
[–7]: Destroy up to X target permanents, where X is the number of lands you control.

Return up to one target nonland permanent to its owner's hand. If you control a creature with flying, surveil 2.

Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
Sword Dance deals 3 damage to target attacking or blocking creature. If you're in a renaissance, Sword Dance deals 5 damage to that creature instead.

When Barbarian Hoarders enters, you may attach target Equipment you control to it.

Destroy target creature or planeswalker. Each player loses life equal to that permanent's mana value.

Destroy all creatures and planeswalkers with mana value X or less.

When Lifebreather enters, you gain 4 life.
Revive {4}{W} ({4}{W}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

Search your library for up to three creature cards with mana value 2 or less, put them onto the battlefield, then shuffle.

This spell costs {X} less to cast, where X is the number of creatures you control.
Vigilance

Whenever Scathing Critics deals combat damage to a player or planeswalker, put a +1/+1 counter on it.

As Sorcerous Spyglass enters, look at an opponent's hand, then choose any card name.
Activated abilities of sources with the chosen name can't be activated unless they're mana abilities.

Augmented — When you cast If Memory Serves, if you've spent {W}{U}{B}{R}{G} to cast spells this turn, copy it twice. You may choose new targets for the copies.
Return target permanent card with mana value 3 or less from your graveyard to the battlefield. Exile If Memory Serves.

Haste
Whenever Spellslinger Elf deals combat damage to a player, draw a card, then you may cast a card from your hand with mana value 3 or less without paying its mana cost.

Whenever you draw a card, put a loyalty counter on Tara, Duneblessed.
[–1]: Create a 1/1 white Soldier creature token. Investigate.
[–2]: If target artifact or creature is tapped, exile it. Otherwise, tap it and put a stun counter on it.
[–10]: Choose up to one creature. Destroy the rest.

When Outside the Airlock enters, create a tapped 3/2 green Horror creature token.
Whenever a creature you control dies, each opponent loses 1 life and you gain 1 life.

Enchant artifact or creature
When Dilapidate enters, tap enchanted permanent.
Enchanted permanent loses all abilities and doesn't untap during its controller's untap step.

Destroy target artifact or enchantment.

Assault {1}{G} (Whenever this attacks, if it has no +1/+1 counters on it, you may pay its assault cost to put a +1/+1 counter on it.)
When Dune Tromper assaults, it gains trample until end of turn.

Gestalt (When this or another creature enters under your control, you may merge it with the one in play, keeping counters and attachments. They become the permanent on top plus all abilities from under it.)
This creature gets +2/+2 and has trample as long as it's merged with another card or token.

Flying
Whenever one or more other creatures die for the first time each turn, journey. (To journey, exile the top card of your library face up. Whenever a creature you control deals combat damage to an opponent, put a journeyed card you own into your hand.)

When Experienced Team enters, choose one —
• Create a 4/2 white Bear creature token.
• Create a 2/4 red Snail creature token.
• Create a 2/2 white Bird creature token with flying.

When Godseeker Vanguard enters, create two 1/1 green Scout creature tokens.

Gestalt (When this or another creature enters under your control, you may merge it with the one in play, keeping counters and attachments. They become the permanent on top plus all abilities from under it.)
Towering Wickerman can't be blocked by creatures with power 2 or less.
Whenever a creature merges with Towering Wickerman, put two +1/+1 counters on it.

Greenheart Den enters tapped.
{T}: Add {G}.
{G}, {T}: Target creature you control gets +1/+1 until end of turn. Activate only as a sorcery and only if you control a green creature.