msem-instigator

Whenever Beragnian Brawlmaster or another Warrior you control enters, that Warrior fights target creature an opponent controls.
{R}{W}: Target Warrior creature gets +1/+1 until end of turn.

Armed — Whenever Beragnian Intimidator attacks, if it's equipped, target creature can't block this turn.

Armed — Beragnian Savage gets +1/+0 and has first strike as long as it's equipped.

Whenever equipped creature attacks, it gets +X/+0 until end of turn, where X is its power.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Create a 3/3 green Beast creature token, then populate. (Create a token that's a copy of a creature token you control.)

Enchant creature
Enchanted creature gets +2/+2 and has lifelink.

Whenever Birthing Elemental or another nontoken creature you control dies, create a 1/1 green Saproling creature token.

When Black Cat dies, target opponent discards a card at random.

When Blade of Reolem dies, target opponent discards a card at random.

Enchant creature (Target a creature as you cast this. This card enters attached to that creature.)
Enchanted creature gets +1/+3.
Whenever enchanted creature attacks, you gain 1 life.

Enchant creature
Enchanted creature gets +3/+3 and has “{G}: Regenerate this creature.”

Enchant land (Target a land as you cast this. This card enters attached to that land.)
Enchanted land has “{T}: Add one mana of any color” and “At the beginning of each upkeep, untap this land.”

When Blightbringer enters, creatures your opponents control get -1/-1 until end of turn.
Unearth {3}{B} ({3}{B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the end step or if it would leave the battlefield. Unearth only as a sorcery.)

Whenever one or more creatures attack you, you may put a -1/-1 counter on target creature.

When Blighting Ooze enters, put a -1/-1 counter on each of up to X target creatures.
As long as Blighting Ooze is on the battlefield, it has all activated abilities of each creature with a -1/-1 counter on it.

Enchant creature
Enchanted creature gets +1/+1 and has hexproof.

Engorge (As this enters, mill three cards, then exile a card from among the milled cards.)
When Blood Servant enters, if it engorged a creature card, you draw a card and you lose 2 life.

Flying (This creature can't be blocked except by creatures with flying or reach.)
When Blood-Tithe Harpy enters, target player loses 1 life and you gain 1 life.

Whenever you sacrifice a creature, you may pay {B}{G}. If you do, put a +1/+1 counter on Bloodblade Mercenary and draw a card.

Engorge (As this enters, mill three cards, then exile a card from among the milled cards.)
When Bloodchill Risen enters, if it engorged an instant card, return target creature to its owner's hand.

Whenever Bloodcrazed Instigator attacks, target Rebel creature you control gains first strike until end of turn.

Haste
When Bloodfury Warlord enters or dies, it deals 2 damage to each player.

Flying
{1}, Sacrifice another creature: Regenerate target Vampire.

Equipped creature gets +1/+1 for each charge counter on Bloodstained Knife.
{2}, Sacrifice a creature: Put a charge counter on Bloodstained Knife.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Trample
Bloodthirsty Berserkers can't be blocked by more than one creature.