msem-instigator

Whenever another creature enters, you gain 1 life.

Whenever another creature enters, you may gain 1 life.

Flying
Whenever Souls of the Jury enters or an opponent fails a trial, create a 1/1 white Cleric creature token.

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.)
If you would gain life, you may put a +1/+1 counter on this creature instead.
When this creature has toughness 20 or greater, you win the game.

Flying
Whenever an enchantment you control enters, target creature you control gets +1/+1 until end of turn.

Lifelink
Revive {W} ({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.)

Flying
At the beginning of your draw step, if Spirit of the Mountains is tapped, put three +1/+1 counters on it.

Flying
Shimmer (Whenever this creature attacks, create a tapped and attacking token that's a copy of it. Exile the token at the beginning of the end step.)

Lifelink
When Stalked Healer enters, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Other creatures you control named Starfall Dancer get +2/+2.

Steelborn Apprentice gets +1/+1 as long as you control an Equipment.

Vigilance
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.)
{T}: Prevent the next X damage that would be dealt to target creature this turn, where X is Steelclad Investigator's power.

Flash
Advance {3}{W} (Cast this for {3}{W} to advance it as it enters. {3}{W}: Advance this as a sorcery.)
Whenever Steelwoven Soldier advances, it gets +2/+2 until end of turn.

Double strike, vigilance, lifelink

{T}: Target creature you control gets +1/+1 until end of turn. Activate only as a sorcery.
Scavenge {W} ({W}, Exile this card from your graveyard: Put a number of +1/+1 counters equal to this card's power on target creature. Scavenge only as a sorcery.)

Flying (This creature can't be blocked except by creatures with flying or reach.)

Melee (Whenever this creature attacks, it gets +1/+1 until end of turn for each opponent you attacked this combat.)
Whenever Tegan, the Sparrowhawk attacks, you may pay {R/W}. When you do, Tegan deals 1 damage to target creature if it's tapped. Otherwise, tap it.

Lifelink
When Telarine Runecarver enters, create a white Aura enchantment token named Relic's Gift attached to target creature. The token has enchant creature and “Enchanted creature gets +1/+1.”

When Thailen's Guard dies, you gain 2 life and scry 1. (To scry 1, look at the top card of your library. You may put that card on the bottom of your library.)

Flying (This creature can't be blocked except by creatures with flying or reach.)
Renown 1 (When this creature deals combat damage to a player, if it isn't renowned, put a +1/+1 counter on it and it becomes renowned.)

Tracking Party enters with a +1/+1 counter on it.
{T}, Remove a +1/+1 counter from Tracking Party and exert it: Destroy target artifact or enchantment. (An exerted creature won't untap during your next untap step.)

Renown 1 (When this creature deals combat damage to a player, if it isn't renowned, put a +1/+1 counter on it and it becomes renowned.)
As long as Traveling Marshal is renowned, it has first strike.

Double strike
Ride {2}{W} ({2}{W}: Transform this and attach it to target creature you control without a Steed. Ride only as a sorcery.)

{T}: Target attacking or blocking creature gets +1/+1 until end of turn.

When Unwitting Fanatic enters, create a 3/2 colorless Horror creature token.
Sacrifice Unwitting Fanatic: Another target permanent you control gains hexproof and indestructible until end of turn.