msem-instigator

Sun-Dappled Paragon enters with a +1/+1 counter on it for each other creature you control.
Whenever another creature you control enters, put a +1/+1 counter on Sun-Dappled Paragon.

Whenever you gain life for the first time each turn, draw a card.
{3}{G}{W}: You gain life equal to the greatest toughness among creatures you control.

When Sunwright Scion enters, put a +1/+1 counter on each other creature you control.
At the beginning of each combat, you may have target creature with a +1/+1 counter on it gain your choice of vigilance, lifelink, or trample until end of turn.

Target creature you control gets +1/+1 and gains lifelink until end of turn. It fights target creature you don't control.

Until end of turn, target creature gets +2/+2, then an additional +2/+2 for each card and token merged with it.

Exile target creature an opponent controls. Each player may search their library for a basic land card and put that card onto the battlefield tapped. Then each player who searched their library this way shuffles.

{8}: Exile target nonbasic permanent. Its controller gains life equal to its mana value.

Flash
When Tenvilu, Earthen Warden enters, other creatures you control get +2/+2 and gain hexproof and indestructible until end of turn.

Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Other permanents you control have hexproof.
Prevent all damage that would be dealt to other permanents you control.

As an additional cost to cast this spell, you may tap any number of creatures you control. This spell costs {1} less to cast for each creature tapped in this way.
Create X 1/1 white Peasant creature tokens. You gain X life. Legendary creatures you control gain hexproof and indestructible until end of turn.

Trample
When The Shepherd of Nowhere enters, each player sacrifices each other nontoken creature they control.
Whenever another nontoken creature you control dies, create a token that's a copy of that creature.

When Thorn Tender enters, rouse 1, then put a +1/+1 counter on each creature you control. (Put a +1/+1 counter on a permanent you control. If it isn't a creature, tap it and it becomes a 0/0 creature in addition to its other types.)

The next creature spell you cast this turn may be cast as though it had flash and costs {1} less to cast. If it entering the battlefield causes a triggered ability of it to trigger, that ability triggers an additional time.

Vigilance
Permanent spells you cast cost {1} less to cast for each 1 damage Tireless Explorer has dealt to players this turn.

Each creature you control enters with an additional +1/+1 counter on it.
When Training Sim enters, create a Function token with “Target creature you control fights target creature you don't control.” (It's an enchantment. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)

Equipped creature gets +2/+2 and has hexproof and vigilance.
Equip {2}

Each player may search their library for a creature card, reveal it, and put it into their hand. Then each player who searched their library this way shuffles it.

Once during each of your turns, you may cast an instant, sorcery, or enchantment spell from your graveyard that targets a creature you control.

{G/W}: If Unlikeliest Heroes doesn't have a +1/+1 counter on it, put a +1/+1 counter on it.
{2}{G/W}{G/W}: If Unlikeliest Heroes has a +1/+1 counter on it and doesn't have vigilance, put two +1/+1 counters and a vigilance counter on it.
{3}{G/W}{G/W}{G/W}: If Unlikeliest Heroes has vigilance and not indestructible, put four +1/+1 counters and an indestructible counter on it.

First mate—There are four or fewer different mana costs among nonland cards in your starting deck. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
First strike
Each spell your opponents cast that would cost less than three mana to cast costs {1} more to cast.

If one or more counters would be put on a creature you control, that many plus one of each of those kinds of counters are put on that creature instead.

Venerated Beast can't be blocked by more than one creature.

Each player chooses an artifact or enchantment they control, then sacrifices the rest.

Level experience, vigilance, trample
Prevent all but the first 1 damage that would be dealt to Verdigris Behemoth each turn. [5/5]
[level 3+] Whenever Verdigris Behemoth deals combat damage to a player, you may destroy target artifact or enchantment that player controls. [7/7]