msem-instigator

Enchant player
At the beginning of each end step, create X 1/1 green Snake creature tokens, where X is the amount of life enchanted player lost this turn.

As an additional cost to cast this spell, sacrifice a creature.
All creatures get -X/-X until end of turn, where X is the sacrificed creature's power.

Exile target creature or planeswalker and all other creatures its controller controls with the same name as that permanent. Search its controller's graveyard, hand, and library for any number of nonland cards with the same name as that permanent and exile them. Then that player shuffles.

Destroy all creatures. Exile all graveyards.

Counter target planeswalker spell.
Draw a card.

Haste
Whenever Banished Companion attacks, it deals 2 damage to you.

Trample
When Bank Skimmer enters, create a green Aura enchantment token named Turtle's Valor attached to target creature. The token has enchant creature and “Enchanted creature gets +X/+X, where X is its mana value.”

Choose two —
• Target player creates two 2/2 white Knight creature tokens with vigilance.
• Destroy target creature with power 4 or greater.
• Target player gains hexproof until end of turn.
• Return target nonland permanent you don't control to its owner's hand.

Trample
Whenever another Dwarf you control enters, create a colorless artifact token named Ale. It has “{T}, Sacrifice this artifact: Target creature gets +2/+0 until end of turn. Activate only as a sorcery.”

When Barhopping in Minei enters, draw up to four cards, then put twice that many drink counters on Barhopping in Minei.
Your maximum hand size is reduced by the number of drink counters on Barhopping in Minei.

First strike (This creature deals combat damage before creatures without first strike.)
Other Soldier creatures you control get +1/+1 and have first strike.
{3}{W}: Create a 1/1 white Soldier creature token.

Barren Boneyard enters tapped.
{T}: Add {B}.
{2/B}{2/B}: Barren Boneyard becomes a 2/3 black Elemental creature with deathtouch until end of turn. It's still a land.

As Barren Desolation enters, you may pay 2 life. If you don't, Barren Desolation enters tapped.
{T}, Sacrifice Barren Desolation: Search your library for a Plains or Swamp card, put it onto the battlefield, then shuffle.

Wither (This deals damage to creatures in the form of -1/-1 counters.)
Whenever Barrow Banshee deals combat damage to an opponent, that player discards a card at random.

Each planeswalker you control enters with an additional loyalty counter on it.
{T}: Add {C}.

Whenever you untap a nonland permanent, put a winding counter on Barton's Pocketwatch.
{T}: Look at the top card of your library. You may put it into your graveyard. Then if Barton's Pocketwatch has twelve or more winding counters on it, exile it and take an extra turn after this one.

Flash
Once each turn, you may cast a spell without paying its mana cost. If you do, at the beginning of your next upkeep, you lose the game unless you pay that spell's mana cost.

Choose one —
• Target creature gets +2/-1 until end of turn.
• Basat Charm deals 3 damage to target player or planeswalker.

Basin Fortress enters tapped unless you control a basic land.
{T}: Add {B} or {G}.

Flying, first strike, vigilance, lifelink
When Bastion Valkyrie dies, create three Function tokens with “Choose a creature targeted by this spell. It gains flying, first strike, vigilance, and lifelink until end of turn.” (They're enchantments. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)

When Batrest's Forgemaster enters, you may search your library for an Equipment card, reveal it, put it into your hand, then shuffle.
Whenever Batrest's Forgemaster attacks, Equipment spells you cast this turn cost {2} less to cast.

Renown 2 (When this creature deals combat damage to a player, if it isn't renowned, put two +1/+1 counters on it and it becomes renowned.)
Whenever a creature you control becomes renowned, draw a card.

Return any number of target creature cards with total mana value X or less from your graveyard to the battlefield, where X is the number of cards in your graveyard. Exile Battle at the Boneyard.

As Battle for the Shield enters, choose Danuri or Fellor.
• Danuri — Soldiers you control get +0/+1 and have vigilance.
• Fellor — Warriors you control get +1/+0 and have first strike.

As Battle the Evil One enters, choose Evil One or Rehison.
• Evil One — Zombie creature cards in your graveyard have unearth {3}{B}. ({3}{B}: Return this card from your graveyard to the battlefield. Exile it at the beginning of the end step or if it would leave the battlefield. Unearth only as a sorcery.)
• Rehison — Whenever an Elf you control enters, you may put a -1/-1 counter on target creature.