Burrog Befuddler

Flash (You may cast this spell any time you could cast an instant.)
When this creature enters, target creature an opponent controls gets -1/-0 until end of turn.

Dispeller's Capsule

{2}{W}, {T}, Sacrifice Dispeller's Capsule: Destroy target artifact or enchantment.

Goblin Firebomb

Flash
{7}, {T}, Sacrifice this artifact: Destroy target permanent.

Minimus Containment

Enchant nonland permanent
Enchanted permanent is a Treasure artifact with "{T}, Sacrifice this artifact: Add one mana of any color," and it loses all other abilities. (If it was a creature, it's no longer a creature.)

Done

Tap up to two target creatures. Those creatures don't untap during their controller's next untap step.

Said

Return target instant or sorcery card from your graveyard to your hand.

Said // Done

Warded Battlements

Defender (This creature can't attack.)
Attacking creatures you control get +1/+0.

Rooting Moloch

When Rooting Moloch enters, exile target card with a cycling ability from your graveyard. Until the end of your next turn, you may play that card.
Cycling {2} ({2}, Discard this card: Draw a card.)

Kinsbaile Courier

When Kinsbaile Courier enters, put a +1/+1 counter on target creature.
Encore {2}{W} ({2}{W}, Exile this card from your graveyard: For each opponent, create a token copy that attacks that opponent this turn if able. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.)

Jack-o'-Lantern

{1}, {T}, Sacrifice Jack-o'-Lantern: Exile up to one target card from a graveyard. Draw a card.
{1}, Exile Jack-o'-Lantern from your graveyard: Add one mana of any color.

Airlift Chaplain

Flying
When Airlift Chaplain enters, mill three cards. You may put a Plains card or a creature card with mana value 3 or less from among the cards milled this way into your hand. If you don't, put a +1/+1 counter on Airlift Chaplain. (To mill a card, put the top card of your library into your graveyard.)