msem-instigator

As Battle the Evil One enters, choose Evil One or Rehison.
• Evil One — Zombie creature cards in your graveyard have unearth {3}{B}. ({3}{B}: Return this card from your graveyard to the battlefield. Exile it at the beginning of the end step or if it would leave the battlefield. Unearth only as a sorcery.)
• Rehison — Whenever an Elf you control enters, you may put a -1/-1 counter on target creature.

Whenever Battle-Scarred Combatant attacks or blocks, put a -1/-1 counter on it.

Flying
When Battlefront Scavenger enters, return target creature card with mana value 3 or less from your graveyard to your hand.

Each creature you control assigns combat damage equal to its toughness rather than its power.
Identity — Other creatures you control get +0/+1 as long as you control at least two other creatures that share a creature type with Battlewise Strategist.

Concord — When Bazaar Equestrian enters, if there are four or more card types among permanents you control, you gain 4 life.

When Bearer of Old Growth enters, choose one —
• Untap up to two target artifacts.
• Draw a card.

When Bearer of Silk Chains enters, gain control of target nonland permanent until Bearer of Silk Chains leaves the battlefield. If that permanent is a Horror, gain control of it instead.

Whenever you detain a permanent, you gain life equal to that permanent's mana value.

Reveal the top three cards of your library. Put all creature cards revealed this way into your hand and the rest into your graveyard.

Desecrate (When this creature enters, you may sacrifice an artifact or land.)
When Beastback Raider desecrates a permanent, discard your hand, then draw three cards.

Menace
When Beatrice enters, target opponent reveals their hand. Exile a nonland card from it. During any turn that player lost life, you may cast that card and mana of any type can be spent to cast that spell.

Counter target spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Concord — When Beetleback Forager enters, if there are four or more card types among permanents you control, return target card from your graveyard to your hand.

All creatures that aren't embattled get -5/-5 until end of turn. If a creature would die this turn, exile it instead. (A creature is embattled if it has a counter on it or a permanent its owner controls attached to it.)

Enchant creature you control
Enchanted creature gets +3/+3.
When Belligerence enters, enchanted creature fights target creature an opponent controls.
When enchanted creature dies, if it's a Warrior, return Belligerence to its owner's hand.

Reprise {4}{G} (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.)
Target creature gets +3/+3 until end of turn. Then create an X/X green Elk creature token, where X is the amount this spell increased that creature's power.

Creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, Bellowing Thoctar gets +2/+2 until end of turn.

Flying
When Benevolent Malach enters, create a 1/1 colorless Construct artifact creature token.
Sacrifice Benevolent Malach: Artifacts you control gain indestructible until end of turn.

[+1]: Creatures you control get +1/+0 and gain haste until end of turn.
[0]: Bennett Brooks deals 2 damage to each opponent. If you have an insight counter, create two Treasure tokens.
[0]: You get an insight counter.
[–2]: Sacrifice an artifact. If you do, return target artifact card from your graveyard to the battlefield.

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.

{1}{G}: Until your next turn, Bessie becomes a 5/5 green Wurm creature with trample, haste, and indestructible. You can't activate this ability while Bessie is being attacked. (She doesn't lose loyalty while she's not a planeswalker.)
[+1]: Creatures you control get +1/+1 and gain haste until your next turn.
[–6]: Create five 3/3 green Wurm creature tokens with trample and haste.

Bestial Mob's power and toughness are each equal to the number of creatures you control.
Whenever Bestial Mob deals combat damage to a player, destroy target creature with toughness less than Bestial Mob's power.

You may have Better Half enter as a copy of any creature on the battlefield, except it's a Reflection in addition to its other creature types and it has distorted. (It can be blocked by tapped creatures but not untapped creatures.)

When Beyond the Boneyard enters, exile another target nonland permanent until Beyond the Boneyard leaves the battlefield.
Your opponents can't cast spells that share a card type with the exiled card during postcombat main phases.

Menagerie — This spell costs {2} less to cast if there are five or more creature types among creatures you control.
Destroy target creature with power or toughness 4 or greater.