msem-instigator

Flying, trample
Whenever Bretala of Redsky attacks, it gains double strike until end of turn unless defending player sacrifices a creature.

Choose a creature type. Return up to two target creature cards of the chosen type from your graveyard to your hand.

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

When Briarform Apothecary enters, create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)
Sacrifice a token: Briarform Apothecary gets +2/+2 until end of turn.

When Briarswine dies, create a 2/2 green Wolf creature token.
Foreshadow {4}{G} (You may cast this spell for its foreshadow cost. If you do, also trigger its “dies” abilities when it enters.)

Hexproof
Whenever attackers are declared, the active player may pay {2} for each creature attacking you. Then you may have Bridge Kalak become an X/X Troll creature until end of turn, where X is the number of times that player didn't pay mana this way.

{T}: Add {C}.
{1}, {T}: Add one mana of any color. This ability costs {1} less to activate if you control three or more basic lands.

Improve {1} ({1}: Put a +1/+1 counter on this creature. This costs {1} more to activate for each +1/+1 counter on it. Improve only as a sorcery.)
When Bridgehaven's Finest enters, create a 1/1 colorless Human creature token.
Other creatures you control get +1/+1 as long as Bridgehaven's Finest has two or more counters on it.

This spell costs {2} less to cast if you control a transformed permanent.
Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

When Bridled Narwhal enters, you gain 5 life.

Prowess
Unveil {2}{U}{R} ({2}{U}{R}: Transform this. Unveil only as a sorcery.)

Lifelink
When Bright-Eyed Adventurer enters, rediscover an enchantment card. (Look at the top card of your library. You may reveal it and put it into your hand if it's an enchantment card. Otherwise, put it back or into your graveyard.)

Spells cost {1} more to cast for each colored mana symbol in their mana cost beyond the first. (For example, a spell with mana cost {W}{W} would cost {1}{W}{W} to cast.)

Flash
When Brightsouled Guardian enters, return up to one target nonland permanent to its owner's hand.

Flying
Whenever you cast a spell from anywhere other than your hand, Brightwing Sphinx gains vigilance until end of turn.

Augmented — Whenever Bril, the Oltenen Emissary enters or attacks, if you've spent {W}{U}{B}{R}{G} to cast spells this turn, destroy target permanent.

Tap up to four target nonland permanents. Nonland permanents your opponents control don't untap during their controller's next untap step.

{T}: Add {C}.
{1}, {T}: Add {W}{U}.

{T}: Add {C}.
{1}, {T}: Add {B}{G}.

{T}: Add {C}.
{1}, {T}: Add {W}{B}.

{T}: Add {C}.
{1}, {T}: Add {U}{B}.

{T}: Add {C}.
{1}, {T}: Add {R}{W}.

{T}: Add {C}.
{1}, {T}: Add {B}{R}.

Prowess, trample
Whenever Brilliant Diviner deals combat damage to a player, draw a card.

Flying
When Brilliant Griffin enters, target creature gets +2/+2 until end of turn.