msem-instigator

Outlands Bodyguard can't attack alone.
You may exert Outlands Bodyguard as it attacks. When you do, it must be blocked this turn if able. (An exerted creature won't untap during your next untap step.)

Flying

Flying, haste
{2}{R}{R}, Exile a multicolored card from your graveyard: Return Rainbow Phoenix from your graveyard to the battlefield tapped. If it's your declare attackers step, it enters attacking.

When Ravenous Abomination enters, choose one —
• Create two Treasure tokens.
• Put a +1/+1 counter on Ravenous Abomination.

Reach
Whenever you cast a spell with mana value 5 or greater, Reaper Squad deals 3 damage to target player or planeswalker.

Trample, haste
When Red Pelt Hart deals combat damage to a player, return it to its owner's hand.
At the beginning of your end step, sacrifice Red Pelt Hart.

Menace
When Santriza Gang-Boss enters, it deals X damage to any target, where X is the number of Pirates and/or Rogues you control.

Flying, haste
Ride {1}{R} ({1}{R}: Transform this and attach it to target creature you control without a Mount. Ride only as a sorcery.)

Trample
Improve {1}{R} ({1}{R}: Put a +1/+1 counter on this creature. This costs {1} more to activate for each +1/+1 counter on it. Improve only as a sorcery.)
Embattled creatures you control get +2/+0. (A creature is embattled if it has a counter on it or has a permanent you control attached to it.)

Improve {1}{B/R} ({1}{B/R}: Put a +1/+1 counter on this creature. This costs {1} more to activate for each +1/+1 counter on it. Improve only as a sorcery.)
At the beginning of each player's combat, you may have that player create two goaded 1/1 red Goblin creature tokens with haste. Exile those tokens at end of combat. (Until your next turn, they attack each combat if able and attack a player other than you if able.)

Menagerie — When Supply Hauler enters, if there are five or more creature types among creatures you control, you may search your library for an artifact card, reveal it, put it into your hand, then shuffle.

Flying
{2}{R}: Target creature attacks this turn if able.

When Thunderstep Ved enters, it deals 1 damage to any target.

Flying
When Trove Keeper dies, create two Treasure tokens.

Flying
Whenever you tap a Mountain for mana, add {R} and that land deals 1 damage to you.
Whenever you tap a non-Mountain land for mana, that land deals 1 damage to Tseng, Warden of the Peak.

{1}, Sacrifice another creature: Crystallize. Activate only as a sorcery. (Put a +1/+1 counter on a creature you control or create a Treasure.)
{W}{U}{B}{R}{G}: Target creature gets +3/+3 and gains trample until end of turn. Activate only as a sorcery.

Trample
When Varagan Packmaster enters, create a Treasure token, then exile the top card of your library. Until the end of your next turn, you may play that card.

Whenever Veiled Charmer attacks, target creature blocks it this turn if able.

Vision (Whenever this or another creature you control enters, reveal the top card of your library. Then you may put that card into your graveyard.)
Whenever Aether Recoverer envisions a creature card, return target noncreature card from your graveyard to your hand.

At the beginning of each upkeep, if no spells were cast last turn, create a 2/2 green Wolf creature token.
{3}{R/G}{R/G}: Albin, the Huntmaster and creature tokens you control get +2/+2 and gain trample until end of turn.

Death knell — Put a trample counter on target creature you control. (As a creature you control dies, trigger one death knell of that creature or another permanent you control.)
Sacrifice a creature: Put a +1/+1 counter on Crushing Victor. Activate only as a sorcery.

Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
{3}{G}: Da'Lang gets +2/+2 until end of turn. If you're in a renaissance, all creatures able to block Da'Lang this turn do so. Activate only once each turn.

Engage (This creature must be blocked each combat if able.)
Whenever Death Pits Gladiator perseveres, profit. (A creature perseveres when it survives damage. To profit, create a colorless Gold artifact token with “Sacrifice this artifact: Add one mana of any color.”)