msem-instigator

Equipped creature gets +1/+0 for each artifact you control.
As long as you control three or more artifacts, equipped creature has flying and haste.
Equip {3}

When Truffle Snuffer enters, mill three cards. When you do, choose one —
• Return an instant or sorcery card put into your graveyard this way to your hand.
• Put two +1/+1 counters on Truffle Snuffer.

Hexproof
Whenever this creature transforms into Tsunami Titan or attacks, you may return target creature to its owner's hand.

Haste
Whenever Tunnel Moles attacks, you may have it phase out. (Treat it and anything attached to it as though they don't exist until its controller's next turn.)
Whenever Tunnel Moles phases in, it gets +2/+2 until end of turn and can't be blocked by creatures with flying this turn.

Archive 5 (As this enters the battlefield, shuffle the top five cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
Eureka! (At the beginning of each end step, you get a research counter if you cast a spell this turn. Then if you have eight or more research counters, remove them and create a Masterpiece token of your choice.)
When you get your eighth research counter, exile Turin's Study, then you may cast any number of nonland cards from the archived library without paying their mana costs.

Hexproof
Whenever Twinning Psionic harnesses an instant or sorcery spell, you may copy that spell. If you do, you may choose new targets for the copy.

Cast this spell only if you have 10 or less life.
Flying, trample

Destroy target artifact or enchantment. You gain life equal to its mana value.

You may have Undecided Mimic enter or phase in as a copy of any creature on the battlefield, except it has this ability and “{2}{U}{U}: Undecided Mimic phases out.” (Treat it and anything attached to it as though they don't exist until its controller's next turn.)

Experience (Whenever this creature attacks, if it has fewer than three +1/+1 counters on it, put a +1/+1 counter on it.)
Unstoppable Weed gets +1/+1 for each +1/+1 counter on other creatures you control.

({T}: Add {B} or {R}.)
Urban Wastelands enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Enchant creature
Harness (You may tap a creature you control as you cast this spell. If you do, reduce this spell's mana cost by that creature's power.)
Enchanted creature gets +3/+0 and has menace.

Flying, protection from Dragons

{T}: Add {C}.
{T}: Add one mana of any color. Activate only if you control a creature with a +1/+1 counter on it.

If two or more creatures an opponent controls are attacking, you may pay {B} rather than this spell's mana cost.
Create a 1/1 black Snake creature token with deathtouch. It gains first strike until end of turn.

Haste
When Volt Vermin enters, it deals damage to target player or planeswalker equal to the number of creatures with flash and/or haste you control.

Deathtouch
When Waking Pollution enters, you may move all counters from target permanent onto Waking Pollution.

Flying
Whenever Wandering Dragonfly or another creature you control enters, you may draw a card. If you do, discard a card.

({T}: Add {G} or {W}.)
Wandering Hamlet enters tapped unless you control two or more basic lands.

Flying
Whenever Warden of Lives attacks, you may cast a creature card from your graveyard. If you do, that creature enters tapped and attacking.
If Warden of Lives would die, it phases out instead.

Flying, vigilance
When Warden of Seas enters, tap all other creatures.
Each opponent can't untap more than one nonland permanent during each of their untap steps.

Flash
Flying
If an effect an opponent controls would cause them to take an extra turn, you take an extra turn instead.
{G}{U}: Return another creature you control to its owner's hand. Activate this ability only once each turn.

Flying, lifelink

When Weaver of Mists enters, substantiate target card in your graveyard. (Put it onto the battlefield face down as a 2/2 creature. You may turn it face up and cast it at any time for its mana cost if it isn't a creature.)
Spells you cast from anywhere other than your hand cost {1} less to cast.

When Weedy Wanderer leaves the battlefield or phases out, put a +1/+1 counter on a creature you control.