msem-instigator

Whenever you cast a noncreature spell, Dynamic Wyvern gains flying until end of turn.

Haste
Whenever Eager Guide attacks, tap up to two target creatures you don't control.

Creatures you control enter with a +1/+1 counter on them if you spend three or more colors of mana to cast them.

When Earthenlore Disciple enters, you may destroy target artifact, enchantment, or land.

First strike
Sacrifice Echo Striker: Target creature gains double strike until end of turn.

{2}{R}, Sacrifice an artifact or land: Draw a card. Edelber Mine Captain deals 1 damage to each opponent.

Trample
Effigy of Harvest gets +1/+1 as long as your fealty to Forests is four or greater. (Each Forest you control counts towards your fealty to Forests.)

Your opponents can't gain life.
Whenever you cast a noncreature spell, put a +1/+1 counter on Eidolon of the Arena.

Indestructible
Whenever a creature you control becomes untapped, draw a card.

Double strike
Whenever Eldan Jackson deals combat damage, return target permanent card with mana value 3 or less from your graveyard to the battlefield.

Whenever Hatsuo attacks, if you control three or more attacking creatures, attacking creatures you control gain first strike until end of turn.
Inspired — Whenever Hatsuo becomes untapped, create a 1/1 white Warrior creature token. It gains haste and attacks this turn if able.

Whenever Chian becomes the target of a spell or ability you control, create a 2/2 blue Drake creature token with flying. This ability triggers only once each turn.

At the beginning of each combat, you may have Elderin, Crystalline Crusader become a copy of another target creature you control with mana value 3 or less until end of turn, except its name is still Elderin, Crystalline Crusader, it's still 3/3, still legendary, and it's an artifact in addition to its other types.
{W}{U}{B}{R}{G}: Elderin gets +3/+3 until end of turn.

When Elemental Loremaster enters, return an instant or sorcery card at random from your graveyard to your hand.

At the beginning of combat on your turn, creatures you control gain your choice of trample, menace, haste, or +1/+0 until end of turn.

At the beginning of your upkeep, you may search your library for a permanent card with mana value 1 or less, put it onto the battlefield, then shuffle.

Flash
{U}, Put Elusive Hunter into its owner's library second from the top: Counter up to one target spell unless its controller pays {2}.

Elfcycling {2}{G} ({2}{G}, Discard this card: Search your library for an Elf card, reveal it, and put it into your hand, then shuffle.)

Haste
At the beginning of your upkeep, sacrifice Ember of Ancient Infernos unless you pay {R}.

Prowess, haste
When Embercore Grazer enters, add {R}{R}{R}. Spend this mana only to cast instant and/or sorcery spells.

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.)
When this creature dies, it deals X damage to target player or planeswalker, where X is the number of cards and tokens merged with it.

Trample
Other Elementals you control get +1/+0 and have trample.

Haste
Other Elementals you control get +1/+0 and have haste.

Trample
Assault {2}{R}{G} (Whenever this attacks, if it has no +1/+1 counters on it, you may pay its assault cost to put a +1/+1 counter on it.)
If one or more +1/+1 counters would be put on a creature you control, that many plus one +1/+1 counters are put on it instead.