msem-instigator

At the beginning of combat on your turn, you may pay {2}{R}{R}. If you do, create a 4/4 red Dragon creature token with flying and haste. Exile that token at end of combat.
Ferocious — Whenever Xiusheng of the Dragon Realm attacks, if you control a creature with power 4 or greater, Xiusheng gains double strike until end of turn.

Menace
Yaran's Enforcer gets +1/+1 as long as you foretold a card this turn.
Yaran's Enforcer gets +1/+1 as long as you cast a foretold spell this turn.

Flying
Whenever Yawning Crane deals combat damage to an opponent, target tapped creature that player controls doesn't untap during its controller's next untap step.

Inspired — Whenever Yenzu Disciple becomes untapped, each opponent loses 1 life and you gain 1 life.

Enchant creature
When Yenzu Puppeteering enters, draw a card.
{1}{U}: Untap enchanted creature.

When Young Chasqui enters, if you cast it, reveal the top five cards of your library. Put any number of creatures named Young Chasqui from among them into your hand. Put the rest of the revealed cards on the bottom of your library in a random order.
A deck can have any number of cards named Young Chasqui.

Wanderlust — Whenever a land you control enters, if you control four or more differently named lands, create a 1/1 green Saproling creature token.

Whenever you cast an instant or sorcery spell, tap target creature an opponent controls.

Whenever a nontoken creature you control dies, create a 1/1 black Skeleton creature token.

Whenever you cast a cryptic spell, create a 1/1 white Human creature token with lifelink. (Artifacts, enchantments, and modal spells are cryptic.)

{T}, Pay 1 life: Add one mana of any color.

Flying
First strike (This creature deals combat damage before creatures without first strike.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Flying (This creature can't be blocked except by creatures with flying or reach.)
When Young Tempter enters, you draw a card and you lose 1 life.

Double strike, haste

Whenever you draw your second card each turn, put a +1/+1 counter on Youthful Tortoise.
Cycling {2} ({2}, Discard this card: Draw a card.)

When Yron Bay Sentinel enters, draw a card.

Archive 2 (As this enters, shuffle the top two cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
Whenever you draw a card from the archived library, target creature you control gains vigilance and indestructible until end of turn.

Whenever you cast a noncreature spell, look at the top X cards of your library, where X is that spell's mana value. Put those cards on top of your library in any order.

Target creature gets +2/+2 and gains lifelink until end of turn.

Choose two —
• Shuffle up to two target cards from graveyards into their owners' libraries.
• Create a 1/1 black Skeleton creature token. You lose 1 life.
• Sacrifice a permanent. Draw a card.

Equipped creature gets +2/+2 and has poisonous 2. (Whenever this creature deals combat damage to a player, that player gets two poison counters.)
Whenever equipped creature attacks, create a 1/1 green Snake creature token with poisonous 1 that's tapped and attacking. Exile that token at end of combat.
Equip {2}

Lifelink
Spells your opponents cast cost an additional {1} to cast for each spell they've cast before it this turn.

Whenever another creature you control leaves the battlefield, put a +1/+1 counter on Zealot of Mahara.
Surpass {5}{W} ({5}{W}: Transform this creature. This costs {1} less to activate for each counter on it. Activate only as a sorcery.)

Voracious 1 (As this enters, you may sacrifice an artifact or creature. If you do, it enters with a +1/+1 counter on it.)
At the beginning of combat on your turn, if you sacrificed a permanent this turn, target creature you control gains trample and haste until end of turn.

Trample
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)