msem-instigator

At the beginning of your upkeep, you win the game if the total mana value of permanents you control is exactly 21. If it's more than 21, sacrifice Gambling Table and all Card tokens you control. Otherwise, create a colorless Card artifact token with mana cost {2} and “{2}, Sacrifice this artifact: Draw a card.”

For any number of target spells or abilities your opponents control, counter it unless its controller pays {4}.

Anomalion enters with a +1/+1 counter on it.
{1}{G}{W}: Permutate. (You may remove a counter from a creature you control. If you do, put two +1/+1 counters on a different creature you control.)

Vigilance
Whenever Karoa's Vanguard or another Knight you control enters, if an opponent controls more lands than you, you may search your library for a Plains card, reveal it, put it into your hand, then shuffle.

Rapport — Whenever Grayce Blaen and at least one other creature you control become tapped, scry 1, then reveal the top card of your library. If it's a land card, you may put it onto the battlefield tapped.

Auditioning for a color causes you to create a 1/1 colorless Construct Actor creature token, then create one of the audition's Role tokens.

Modular Mercenary gets +1/+0 and has first strike as long as you control a creature with a +1/+1 counter on it.

Look at the top five cards of your library. You may reveal a land or enchantment card from among them and put it into your hand. Then put the rest on the bottom of your library in any order.

Menace, haste
Whenever Tiger of the Drums attacks, choose one —
• Exile target opponent's graveyard.
• You draw a card and lose 1 life.
• Torment each opponent. (They lose 3 life unless they discard a card or sacrifice a nonland permanent.)

Archive 6 (As this enters, shuffle the top six cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
You may play Aura and Equipment cards from the archived library, and play those spells as though they had flash.

Spells cost {3} more to cast this turn.
Activated abilities that aren't mana abilities cost {3} more to activate this turn.

Slay Them in the Aisles deals 2 damage to each non-Actor creature.

Vigilance
Whenever Underpass Sentinel enters or attacks, you may put a +1/+1 counter on another target creature you control without one.
Sacrifice Underpass Sentinel: Embattled creatures you control gain hexproof and indestructible until end of turn. (A creature is embattled if it has a counter on it or a permanent you control attached to it.)

({T}: Add {G} or {W}.)
Alpine Meadow enters tapped.

Wu Xing (Add effects based on the number of colors of mana spent to cast this spell.)
1 | Refulgent Flare deals 3 damage to any target. If a permanent dealt damage this way would die this turn, exile it instead.
3 | You gain 3 life.

Flying
Whenever Searshot Dragon deals combat damage to a player, it deals that much damage to target creature that player controls.
{1}{R}: Searshot Dragon gets +1/+0 until end of turn.

Pressure—{B}, Exile six cards from your graveyard. (You may cast this spell for its pressure cost if there are seven or more cards in your graveyard.)
Deathtouch
{B}, Exile six cards from your graveyard: Return Danithra Champion from your graveyard to the battlefield. Activate only during your turn.

Indestructible
Whenever this creature enters or transforms into Mahara, recruit. (Create a 0/0 white Soldier Army creature token, then put a +1/+1 counter on each Army you control.)
At the beginning of your end step, if you control four or more creatures, transform Mahara.

Double strike

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.)
Double strike
If this creature would deal noncombat damage, it deals double that damage instead.

Senaturian Legion gets +1/+1 for each other creature on the battlefield named Senaturian Legion.
A deck can have any number of cards named Senaturian Legion.

Destroy target creature with flying.

Enchant creature
Whenever enchanted creature attacks, other creatures you control get +1/+2 until end of turn.

Vigilance, reach
Tahti, Forged by the World gets +1/+1 for each other creature you control.
Other creatures you control get +1/+1.