msem-instigator

{2}{R}: Ruthless Mastiff gets +3/+0 until end of turn.

Whenever one or more creatures you control deal combat damage to a player, you may discard a card. If you do, draw a card.
{2}{R}, {T}, Exile two cards from your graveyard: Sarrutu Flamebinder deals 2 damage to any target.

Prowess
Each instant and sorcery card with mana value 3 or less in your hand has inscribe. The inscribe cost is equal to its mana cost increased by {1}{U/R}. (Pay that card's mana cost increased by {1}{U/R}: Exile that card from your hand inscribed on a creature you control. Whenever that creature attacks, its controller may cast a copy of the inscribed card without paying its mana cost. Inscribe only as a sorcery.)

Colossal 3—{4}{R} (You may cast this for its colossal cost to have it enter with three +1/+1 counters; or pay {4}{R} as a sorcery: Put three +1/+1 counters on it if it has none.)
When Storm-Eye Salamander's colossal ability puts one or more counters on it, exile the top three cards of your library. Until the end of your next turn, you may play one of those cards.

Menace, prowess

Temple Recluse gets +1/+0 as long as you've cast a noncreature spell this turn.

Ferocious — When Volcanic Whelp enters, if you control a creature with power 4 or greater, Volcanic Whelp gets +3/+0 and gains haste until end of turn.

Prowess
{1}{R}: Until end of turn, if an instant, sorcery, or Dragon source you control would deal damage to a permanent or player, it deals that much damage plus 1 to that permanent or player instead. Activate only once each turn.

Whenever Wandering Conqueror attacks, it explores. (Reveal the top card of your library. Put it into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then you may put that card in your graveyard.)
As Wandering Conqueror explores a land, you may put that card into your graveyard. Whenever you do, Wandering Conqueror deals 2 damage to target player or planeswalker.

Whenever you cast a spell, Wandering Precursor gets +1/+0 until end of turn for each color of mana spent to cast that spell.

Double strike, haste

When Alder Courtier dies, you gain 4 life.

Trample
{T}, Sacrifice another creature: You gain 3 life.
Whenever another creature you control dies, put a +1/+1 counter on Bloodbriar Archdruid.

Erratic (When this creature dies, reveal the top four cards of your library. Put a creature card that costs less than this revealed this way onto the battlefield and the rest on the bottom of your library in any order.)

When Bubbledome Chorister enters, create a green Aura enchantment token named Sanctum's Gift attached to target creature. The token has enchant creature and “Enchanted creature has ‘{T}: Add {G} for each enchanted creature you control.'”

Deathtouch
Cadence (Whenever you cast a spell, if its mana value is greater than this creature's power, put a +1/+1 counter on this creature.)

Whenever another creature named Crinster Sheepdog enters, nourish 1. (To nourish 1, either put a +1/+1 counter on this creature or create a 1/1 white Citizen creature token.)

Reach
When Danaj Decider dies, judge another target creature you control. (Honor it by putting a +1/+1 counter on it or condemn it by sacrificing it to draw a card.)

Landfall — Whenever a land you control enters, Duskwood Vanguard gets +1/+1 until end of turn.

When El, Humble Apprentice enters, search your library for a basic land card, reveal it, put it into your hand, then shuffle.
Chosen one ({W}{U}{B}{R}{G}: Transform this permanent.)

Improve {1} ({1}: 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.)
{T}: Add one mana of any color.
{T}: Add X mana of any one color, where X is the greatest number of counters among creatures you control.

Wanderlust — Feral Ornithax gets +2/+2 and has trample as long as you control four or more differently named lands.

You may play lands from your graveyard.
Whenever a land you control enters, create a 1/1 white Peasant creature token.

When Glowskate Channeler enters, create a green Aura enchantment token named Manta's Wings attached to target creature. The token has enchant creature and “Enchanted creature gets +2/+2.”

Whenever you cycle a card, reveal the top two cards of your library. You may put a permanent card from among them into your hand. Put the rest on top of your library in any order or into your graveyard.
Cycling {2} ({2}, Discard this card: Draw a card.)