msem-instigator

Vithian Arcanist gets +2/+0 and has haste as long as you've cast an instant or sorcery spell this turn.
When Vithian Arcanist enters, add {U}{B}{R}. Spend this mana only to cast instant and/or sorcery spells.

When Volcano Elemental dies, it deals 2 damage to any target.

Double strike
The first spell you cast during each of your turns costs {W}{U}{B}{R}{G} less to cast. This effect reduces only the amount of colored mana you pay.

Flash
Enchant creature
Enchanted creature gets +3/+3.
Cycling {2} ({2}, Discard this card: Draw a card.)

When Conduit of the Conflux enters, scry 2.
{T}: Add one mana of any color.

{4}{G}, Sacrifice Elvish Godtracker: Create a 5/5 green Beast creature token.

Stampede — Whenever Exuberant Hunter and a creature with greater power attack, draw a card.

{3}{R}: Target creature can't block this turn.

Deathtouch
When Flesheater Vine enters, you may have it consume. If you do, put a +1/+1 counter on it and you gain 3 life. (To consume, sacrifice another creature or exile a creature card from your graveyard.)

Target creature you control deals damage equal to its power to target creature you don't control. Scry 1.

Create three 1/1 green Saproling creature tokens.

Trample
Cycling {2} ({2}, Discard this card: Draw a card.)

At the beginning of your upkeep, create a 1/1 green Saproling creature token.
Whenever a creature you control dies, put a +1/+1 counter on Heart of Spores.
{X}{G}: Move X +1/+1 counters from Heart of Spores onto target creature. Activate only as a sorcery.

Encourage ({T}: Another target creature you control gets +1/+1 until end of turn. Encourage only as a sorcery.)
{T}: Add {G}.
Whenever Hierarch Ranger encourages a creature, add one mana of any color.

{1}{R}: Exile the top card of your library. If it's a creature card, you may play it until the end of your next turn.
{4}{W}: Put two +1/+1 counters on target creature.

Knight of the Olive Orchard can't be blocked by more than one creature.

Stampede — Whenever Knotvine Preserver and a creature with greater power attack, until end of turn, attacking creatures you control gain “When this creature dies, return it to its owner's hand.”

Encourage ({T}: Another target creature you control gets +1/+1 until end of turn. Encourage only as a sorcery.)
Whenever Leotau Rider encourages a creature, that creature gains trample until end of turn.

Choose one —
• Destroy target artifact.
• Lichen's Grasp deals 4 damage to target creature with flying.
Cycling {2} ({2}, Discard this card: Draw a card.)

Trample
Other Beasts you control have trample.
Whenever Magnoceros attacks, create a 5/5 green Beast creature token that's tapped and attacking.

Hexproof
Mist-Valley Ancient enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Vigilance
Mountaincycling {1}, plainscycling {1} ({1}, Discard this card: Search your libary for a Mountain or Plains card, reveal it, put it into your hand, then shuffle.)

Creatures you control get +3/+3 until end of turn.
Cycling {2} ({2}, Discard this card: Draw a card.)

Reach
Stampede — Whenever Qasali Quiverguard and a creature with greater power attack, untap all attacking creatures.

At the beginning of combat on your turn, you may have Regurgitator Ooze consume. If you do, it gets +2/+2 until end of turn. (To consume, sacrifice another creature or exile a creature card from your graveyard.)
When Regurgitator Ooze dies, return a card exiled with it to its owner's hand.