msem-instigator

Submerge each creature you control. At the beginning of the next end step, you may turn any number of face down creatures you control face up. (To submerge a card, exile it, then put it on the battlefield face down under its owner's control as a 2/2 creature.)

When you cast your third noncreature spell each turn, transform Aspiring Rascals.

{2/G}, {T}: Put a +1/+1 counter on target creature you control.

Wither (This deals damage to creatures in the form of -1/-1 counters.)
{1}{B}: Return Noonfiend from your graveyard to your hand.

{1}: Danaj Sightseer gains lifelink until end of turn if {W} was spent to activate this ability. The same is true for flying and {U}, menace and {B}, first strike and {R}, and trample and {G}.
At the beginning of your end step, if you've spent {W}{U}{B}{R}{G} to cast spells and/or activate abilities this turn, put three +1/+1 counters on Danaj Sightseer.

{7}, {T}, Sacrifice Samaki School: Look at the top four cards of your library. Put two into your hand and the rest on the bottom of your library in any order.

Lionize {2}{U} ({2}{U}, Exile this card from your hand: Put a +1/+1 counter on target creature and it gains the following ability until end of turn. You may cast this card on a later turn from exile.)
Whenever this creature deals combat damage to a player, draw that many cards.

Rapport — Whenever Memorial of Forgotten Heroes and at least one other creature you control become tapped, put a +1/+1 counter on one of those creatures.
{T}, Tap an untapped creature you control: Add one mana of any color.

Exile target enchantment or Equipment.

Ferocious — When Pack Familiar dies, if you control a creature with power 4 or greater, create two 2/2 green Wolf creature tokens.

{T}: Add one mana of any color. Spend this mana only to cast an instant or sorcery spell.

Enchant player
When Curse of Fangs enters, gain control of target creature enchanted player controls. It becomes a Vampire in addition to its other types.
Creatures attacking enchanted player have lifelink.

({T}: Add {W} or {B}.)
Whenever Arctic Mine becomes tapped, you lose 1 life unless you control two or more basic lands.

{T}, Sacrifice Evolving Wilds: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Deathtouch
When Mire Triton enters, mill two cards and you gain 2 life.

Return target instant or sorcery card with mana value 3 or less and without reconstruct from your graveyard to your hand.
Reconstruct {6}{U} (You may cast this from your graveyard for its reconstruct cost reduced by the mana value of a permanent you sacrifice as you cast it this way. Then exile this.)

Menace
When Darna's Atrocity enters, you may pay 2 life. If you do, you draw two cards and mill two cards.
{B}, Exile a card from your graveyard: Darna's Atrocity gets +1/+1 until end of turn.

Whenever you activate a loyalty ability of a planeswalker, you gain 1 life.

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

Discard two cards, then draw a card for each card discarded this way. Night of Falling Stars deals damage equal to the total mana value of the discarded cards to each creature.

Equipped creature gets +2/+2 and has ward {2} and “Whenever this creature attacks, draw a card, then you may put a land card from your hand onto the battlefield.”
Equip {2}

At the beginning of combat, each player chooses a creature. Those creatures attack or block this turn if able. Whenever one of those creatures dies this turn, Sweep Stakes deals 3 damage to that creature's controller.

Shadow Ball deals 2 damage to target creature or planeswalker and 2 damage to its controller. You gain 2 life.

Flying, double strike
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

When Kahroba General enters, recruit. (Create a 0/0 white Soldier Army creature token, then put a +1/+1 counter on each Army you control.)
Kahroba General gets +1/+1 for each creature you control.