msem-instigator

Whenever an opponent discards a card, you may draw a card.

Reprise {3}{B} (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.)
This spell deals 2 damage to target creature. You gain life equal to the total damage dealt by this spell.

Look at the top four cards of your library. You may reveal a noncreature card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

{T}: Add {C}.
{T}, Sacrifice Shiftscape Crag: Choose a basic land type other than Mountain. Create a colorless land token that's a Mountain and the chosen basic land type. Activate only during your upkeep.

Equipped creature gets +1/+1 and has flying.
Equip {2}

Return target creature card from your graveyard to the battlefield tapped. Then create a token that's a copy of it, except it has haste. Sacrifice the token at the beginning of the next end step.

Master Assassin can't be blocked by creatures with odd mana values. (Zero is even. This creature's mana value is 2.)
Whenever you cast a spell during an opponent's turn, put a +1/+1 counter on Master Assassin. You may have it phase out.

Flash
When Fiery Truthseeker enters, you may cast target instant or sorcery card with mana value 3 or less from your graveyard without paying its mana cost. If that spell would be put into your graveyard, exile it instead.

Scry 1, then draw two cards. You gain 3 life. Exile up to four cards from graveyards.

Trample, hexproof
Renown 4 (When this creature deals combat damage to a player, if it isn't renowned, put four +1/+1 counters on it and it becomes renowned.)
{1}{G}: Target creature blocks Tsolmon, the Huntress this turn if able.

Defender
Whenever Derelict Watcher or another Scarecrow you control enters, create a 1/1 black Bird creature token with flying.

Whenever Talent Scout enters or dies, return target creature card with mana value 2 or less from your graveyard to your hand.

As an additional cost to cast this spell, sacrifice a permanent.
When Harriet, Liberated Wildborn enters, you may remove all counters from target permanent.

Inspired — Whenever Pon's Apprentice becomes untapped, target creature you control has base power and toughness 5/5 until end of turn.

Whenever an opponent casts their first spell each turn, that player may pay {1}. If they don't, you may create a Treasure token and you may draw a card.

Target player draws X cards and loses X life.

Equipped creature gets +1/+1 and has lifelink.
Whenever equipped creature dies, if it wasn't a token, you may pay {3}. If you do, create a token that's a copy of that creature and attach Bloodguard's Hand to it.
Equip {3}

Whenever another nontoken creature you control enters, that creature gains haste until end of turn. Then Tremor Seer deals 1 damage to any target.

Whenever you cast a spell during an opponent's turn, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

({T}: Add {U} or {B}.)
As Ruptured Grotto enters, you may pay {1}. If you don't, Ruptured Grotto enters tapped.

{T}: Add {U}, {B}, or {R}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Tap target creature. It doesn't untap during its controllers next untap step.
Judge target creature you control. (Honor it by putting a +1/+1 counter on it or condemn it by sacrificing it to draw a card.)

{T}, Sacrifice Rootshambler: Untap all basic lands you control.

Flying
At the beginning of your upkeep, you may create a token that is a copy of target Aura you control and attach it to target permanent or player it could enchant.
{2}, Sacrifice an Aura: Artiaburz gains indestructible and hexproof until end of turn.

Whenever a +1/+1 counter is put on Lifeblood Leecher, target creature an opponent controls gets -1/-1 until end of turn.