msem-instigator

Target creature you control gets +1/+0 until end of turn. It deals damage equal to its power to another target creature.

{2}{R}, Sacrifice an artifact or creature: It deals 2 damage to any target.

Flying
Vanishing 3 (This creature enters with three time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
If Chronowing Phoenix would die while it had no time counters on it, instead exile it, then return it to the battlefield.

Armed — Other Goblin creatures you control get +1/+1 and have haste as long as Clanleader of Beragnos is equipped.

Destroy target land. Continental Collapse deals 2 damage to that land's controller.

Trample
Whenever Crazed Wildlings deals combat damage to a player, create a 1/1 red Goblin creature token.

Trample, haste
When Dashing Rager enters, attach all Equipment on the battlefield to it. (Control of the Equipment doesn't change.)
At the beginning of the end step, sacrifice Dashing Rager.

Prowess
Vanishing 2 (This creature enters with two time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)

Until end of turn, whenever you cast an instant or sorcery spell, you may discard a card. If you do, draw a card.

At the beginning of your upkeep, exile the top card of your library. Until end of turn, you may play that card if it's an instant or sorcery card.

Vanishing 3 (This creature enters with three time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
When Fickleflame Summon enters or leaves the battlefield, draw a card, then discard a card.

Attacking creatures you control have “{R}: This creature gets +1/+0 until end of turn.”
Armed — Whenever Forgeborn Barbarian attacks, add {R} for each equipped creature you control.

Search your library for an Equipment card, reveal it, put it into your hand, then shuffle.

Gain control of target creature until end of turn. Untap that creature. Until end of turn, it gets +1/+0 and gains haste.

When Goblin Twinblades enters, create a 1/1 red Goblin creature token.

Armed — Whenever Hordedriver Enthusiast attacks, if it's equipped, creatures you control get +1/+0 and gain trample until end of turn.

Destroy target artifact.
Reprise {R} (As you cast an instant or sorcery spell, you may exile one card with reprise from your graveyard and pay its reprise cost. If you do, add its effects to that spell.)

Enchant creature
Enchanted creature gets +3/+0 and has haste and menace.

Cast Khalizors' Last Stand only during your postcombat main phase.
Gain control of target creature until end of turn. Untap all creatures you control. They gain haste until end of turn. After this phase, there is an additional combat phase followed by an additional main phase.

[+1]: Search your library for a Mountain card, reveal it, put it into your hand, then shuffle.
[–2]: Koth, One True Hero deals damage to target creature equal to the number of Mountains you control.
[–7]: Create X 3/1 red Elemental creature tokens with trample and haste, where X is the number of Mountains you control.

Koth's Retaliation deals 4 damage to target creature. When that creature dies this turn, exile its controller's graveyard.

Vanishing 1 (This creature enters with a time counter on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
Whenever a creature you control deals combat damage to a player, put a time counter on Lavacore Elemental.

Armed — Merciless Brute gets +2/+2 as long as it's equipped.

Meteor Volley deals 3 damage to each creature.
Reprise {4}{R}{R} (As you cast an instant or sorcery spell, you may exile one card with reprise from your graveyard and pay its reprise cost. If you do, add its effects to that spell.)

Mill three cards. Pyromancer's Fury deals damage to any target equal to the number of instant and sorcery cards in your graveyard.