msem-instigator

As Nimble Sandstorm enters, choose speed or power.
At the beginning of combat on your turn,
• Speed — Target creature gains haste until end of turn.
• Power — Target creature gets +2/+0 until end of turn.

When Ninhasir's March enters, it deals 3 damage to any target.
{1}{R}{R}: Transform Ninhasir's March. Activate only if your fealty to Mountains is five or greater.

Indestructible
When this creature transforms into Ninhasir, God of Creation, discard all the cards in your hand, then draw that many cards plus one.
Whenever you cast an instant or sorcery spell, copy it. You may choose new targets for the copy.

Nip at the Heel deals 1 damage to any target. Create a 1/1 red Hound creature token.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When Nizev Brawler enters, target creature can't block this turn.

Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)
Whenever you cast an enchantment, instant, or sorcery spell, Noble Barracuda gets +1/+0 until end of turn. Scry 1.

At the beginning of each player's upkeep, Noble's Hedonism deals 1 damage to that player, then that player exiles the top card of their library. Until end of turn, they may play that card.

Shimmer (Whenever this creature attacks, create a tapped and attacking token that's a copy of it. Exile the token at the beginning of the end step.)
Whenever you cast an instant or sorcery spell, Noirohpo Renegade gets +1/+0 until end of turn.

Flying
Whenever Novaheart Dragon enters or attacks, you may take an extra turn after this one. If you do, you lose the game at the beginning of that turn's end step.

Flying
When Novaheart Guardian enters, it deals 4 damage to any target.
Whenever a creature or planeswalker dies, put a +1/+1 counter on Novaheart Guardian.

Whenever you cast a noncreature spell, Novice Pyromancer deals 1 damage to target player or planeswalker.

As an additional cost to cast this spell, you may discard two cards. If you do, this spell costs {3} less to cast and it can't be countered.
Exile the top three cards of your library. You may play those cards until the end of your next turn.

Null Bit deals 3 damage to any target.
You may discard a card. If you do, draw a card.

Menace
Whenever you cast a glitched spell, Null Entity gets +2/+0 until end of turn for each time that spell was glitched.

Survivors you control have haste.

Menace
When OM-6 Walker dies, OM-6 Walker deals damage to each player equal to twice the number of nonbasic lands that player controls.

Oathbreaker Orc attacks each combat if able.
Whenever Oathbreaker Orc attacks, it deals 2 damage to defending player unless that player sacrifices a permanent.

{T}: Put a luster counter on Object of Awe.
{1}{R}, {T}: Discard up to X cards, then draw a card for each card discarded this way. X is the number of luster counters on Object of Awe.
{3}{R}: Until end of turn, Object of Awe becomes an X/X red Phoenix creature with flying, where X is the number of luster counters on Object of Awe.

Obliterating Blast deals 3 damage to any target. A creature dealt damage this way this turn can't be regenerated this turn. If that creature would die this turn, exile it instead.

Obscoriate deals 4 damage to target creature or planeswalker. The next time that permanent would die this turn, instead put a basalt counter on it, it becomes a Mountain land named Charred Remains, loses all other card types, and gains “At the beginning of your upkeep, Charred Remains deals 1 damage to you.” (It has “{T}: Add {R}” and loses abilities it already had.)

Flying
When Obsidian Hellkite dies, it deals 2 damage to up to one target creature or planeswalker. If that creature or planeswalker would die this turn, exile it instead.
Foreshadow {4}{R}{R} (You may cast this spell for its foreshadow cost. If you do, also trigger its “dies” abilities when it enters.)

Whenever you attack, you may double target attacking creature's power. If you do, sacrifice it at the beginning of the next step.
Whenever one or more red creatures you control enter, creatures you control get +1/+0 and gain trample until end of turn.

Ode to the Red Wind deals 1 damage to target creature. It can't block this turn.
Showcase {3}{R} (Then if you cast this for its showcase cost, create a 1/1 red Bard creature token that can't block and exile this. Whenever it attacks, you may cast a free copy of this.)

You may pay {R} and tap an untapped Warrior you control rather than pay this spell's mana cost.
Choose one —
• Double the power of target creature you control until end of turn.
• Target creature you control deals damage equal to its power to target creature or planeswalker.

Trample, haste
When Oil Driller enters, salvage two cards at random. (Exile those cards from your graveyard until this creature leaves the battlefield. Whenever this creature deals combat damage to a player, put a card it salvaged into your hand.)
At the beginning of your end step, sacrifice Oil Driller.