msem-instigator

Whenever Breakneck Barque becomes blocked by a creature, Breakneck Barque deals 3 damage to that creature.
Crew 3 (Tap any number of creatures you control with total power 3 or greater: This Vehicle becomes an artifact creature until end of turn.)

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

This spell costs {1} less to cast for each artifact and/or enchantment you control.

{6}{U}: Brume Trench-Thrasher can't be blocked this turn. This ability costs {1} less to activate for each instant and sorcery card you own in exile and in your graveyard.

Deathtouch
Once each turn, you may cast a creature spell from your graveyard by paying life equal to its mana value rather than paying its mana cost.

Whenever Byway Bruiser enters or leaves the battlefield, you may have it deal 3 damage to any target.

Trample
{2}{G}{G}: Put Canal Lurker from its owner's graveyard on top of its owner's library.

Vigilance
Resolute — Canopy Stomper can't be blocked by creatures with power 2 or less as long as Canopy Stomper's power is greater than its base power.

Flying, haste
Whenever Cheng attacks, look at the top six cards of your library. You may reveal a creature card from among them and put it into your hand. If it's a Dragon, put it onto the battlefield tapped and attacking instead. Put the rest on the bottom of your library in a random order.

Children of the Void has hexproof as long as it's your turn.
Children of the Void can't attack or block unless you reappropriate (exile exactly two cards from your hand and/or graveyard).

Search your library for up to two basic land cards, reveal those cards, and put one onto the battlefield tapped and the other into your hand, then shuffle.
Coalesce {7}{G} (You may cast this from your graveyard for {7}{G}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)

Trample
If one or more counters would be put on a permanent you control, three times that many counters are put on that permanent instead.

Combined Generator can't be blocked except by three or more creatures.

This spell costs {1} less to cast for each Desert you control.
When Crested Crustacean enters, return target permanent to its owner's hand.

Creatures you control get +4/+4 and gain trample until end of turn.
Coalesce {8}{G}{G} (You may cast this from your graveyard for {8}{G}{G}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)
Trample

Flying
Breach (Whenever this deals combat damage to a player, you may have it become an Aura Curse until your next turn. Attach it to that player.)
Whenever a cursed opponent draws a card, you may draw two cards.

Vigilance, reach
When DL-19 Reject enters, target creature you control gets +2/+2 until end of turn.

Mark (Whenever this creature attacks, mark target creature until end of turn.)
Whenever a marked creature an opponent controls dies, create a Food token. (It's an artifact with “{2}, {T}, Sacrifice this artifact: You gain 3 life.”)

Bloodprice {4}{B} (You may cast this card by sacrificing a creature and paying its bloodprice.)
At the beginning of your upkeep, if there are five or more creature cards in your graveyard, create a 2/2 black Demon creature token.

Deep-Sea Terror can't attack unless seven or more cards are in your graveyard.

This spell costs {2} less to cast for each creature that died this turn.
Flying, trample

{1}{B}, Sacrifice another creature: Draw a card and create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)
{2}{B}, Sacrifice three Idols: Return Demon of Hubris from your graveyard to the battlefield. Activate only as a sorcery.

Desert Wurms can't be blocked by creatures with flying.
When Desert Wurms enters, create two 6/6 red Wurm creature tokens with “This creature can't be blocked by creatures with flying.”
When Desert Wurms is put into a graveyard from anywhere, shuffle it into its owner's library.

Hexproof

Lionize {U}{R}{W} ({U}{R}{W}, 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 or noncreature permanent, return target noncreature card from your graveyard to your hand.