msem-instigator

Flying, prowess
Whenever Surveyor of Skies attacks, you may return a permanent you control to its owner's hand.

When this creature enters, target creature you control gets +1/+1 and gains vigilance until end of turn. You may remove a counter from that creature.

First strike
Whenever Ren deals combat damage to a player, you may activate one of her abilities by paying 3 life rather than paying its cost.
{1}{R}, Discard a card: Draw a card.
{2}{B}, Sacrifice a creature: Each opponent sacrifices a creature.

Flying, first strike
When Swiftclaw Griffin enters, return a creature you control to its owner's hand.

Hexproof (This creature can't be the target of spells or abilities your opponents control.)

Swiftstep Cliffdweller has haste as long as you control another Goblin.

Whenever you cast a red spell, create a 2/1 red Merfolk creature token.
Whenever you cast a green spell, target creature gets +2/+2 and gains trample until end of turn.

When Symbiotic Sprout dies, create two 1/1 green Saproling creature tokens.

When Syncretic Master enters, look at the top X cards of your library, where X is the number of basic land types among lands you control. Put one them into your hand and the rest into your graveyard.

Syndicate Sycophant can't block.
When a creature you control scavenges Syndicate Sycophant, you may search your library for a card named Syndicate Sycophant, reveal it, put it into your hand, then shuffle.
Scavenge {2}{B} ({2}{B}, Exile this card from your graveyard: Put a number of +1/+1 counters equal to this card's power on target creature. Scavenge only as a sorcery.)

Whenever a creature you control becomes blocked, you may return it to its owner's hand.
The first spell you cast during your postcombat main phase each turn costs {W}{U} less to cast. This effect reduces only the amount of colored mana you pay. (For example, if you cast a spell with mana cost {1}{U}, it costs {1} to cast.)

Flying
When Syrina's Brood enters, look at the top six cards of your library, then put them back in any order.

When Syzygy Navigator enters, exile target nonland card from an opponent's graveyard. Copy it. You may cast the copy. (You still pay its costs, including color. Copies of permanents enter as tokens.)
Whenever you cast a spell from anywhere other than your hand, draw a card, then discard a card.

During each of your turns, you may cast a copy of a card in an opponent's graveyard by exiling that card in addition to its other costs. (Copies of permanents enter as tokens.)

Augmented — When TD-3 Slyten Retriever enters, if it's not a token and you've spent {W}{U}{B}{R}{G} to cast spells this turn, create a token that's a copy of it.
When TD-3 Slyten Retriever dies, draw a card and gain 3 life.

Flying
Other creatures you control with flying get +1/+0.

Flash
First strike
If you cast Taiyohata Champion during your declare attackers step, it enters tapped and attacking.

Spirited (When this creature enters, you may activate one of its activated abilities without paying its cost.)
{6}{R}: Takara Flameblade deals 4 damage to target creature. Activate only once each turn.

Flying
As Tal, Locus Sentry enters, choose a noncreature, nonland card type.
Spells of the chosen type cost {1} more to cast.

Whenever Talent Scout enters or dies, return target creature card with mana value 2 or less from your graveyard to your hand.

Menace
Whenever Tamaak's Mouth attacks, defending player sacrifices a nonland permanent.

Trample
{3}{B}{G}, Discard two cards: Return Tammil and Sulei, the Guides and another target creature card from your graveyard to the battlefield tapped.

When Tantalizing Glutton enters, create a green Aura Curse enchantment token named Just Out of Reach attached to target player. The token has enchant player and “At the beginning of each of enchanted player's opponents' upkeeps, if that player doesn't control a Food, they create a Food token.”

Deathtouch
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 an opponent has less life or fewer cards in their main library than the number of Curses attached to them, they lose the game.