msem-instigator

Whenever an enchantment enters the battlefield under your control, target opponent loses 1 life and you gain 1 life.

Weeping Lotus enters the battlefield with five petal counters on it.
At the beginning of your upkeep, remove a petal counter from Weeping Lotus. If you do, create a colorless artifact token named Lotus Petal with “{T}, Sacrifice this artifact: Add one mana of any color.”

Lifelink
Whenever you gain life, each opponent loses 1 life.

Flying
Welkin Tern can block only creatures with flying.

As an additional cost to cast this spell, sacrifice a creature.
Search your library, hand, or graveyard for a creature card with mana value 1 greater than the sacrificed creature's and put it onto the battlefield. If you searched your library this way, shuffle.

Augmented — If you've spent {W}{U}{B}{R}{G} to cast spells this turn, you may cast this spell without paying its mana cost.
Counter target spell.

Draw two cards, then discard two cards. Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Whenever you draw a card, target player mills two cards.
Whenever you cast a blue spell, scry 1, then you may reveal the top card of your library. If it's an instant or sorcery card, draw a card.

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.)
Return each nonland permanent your opponents control to its owner's hand.

This spell costs {2} less to cast if it targets a creature or planeswalker card with mana value 3 or less.
Return target creature or planeswalker card from your graveyard to the battlefield.

Create a 1/1 white Spirit creature token with flying.
Whenever a nontoken creature you control dies, you may pay {W} and exile Whispered Wishes from your graveyard. If you do, create a 1/1 white Spirit creature token with flying.

Whispering Canal enters the battlefield tapped unless you control a basic land.
{T}: Add {U} or {B}.

Mill three cards. When you do, return a nonland card from your graveyard to your hand.

When Whistling Blades enters the battlefield, you may destroy target creature or planeswalker.
Recite {1}{B}{B} (You may cast this creature from your graveyard for its recite cost. If you do, exile it when it enters the battlefield or if it would leave the battlefield.)

Double strike

{T}: Add {C}.
{9}, {T}, Exile Whiterun Gates: Take an extra turn after this one.

{T}: Add {C}.
{T}: Each opponent may draw a card. For each player who does, draw a card.

Target creature gains lifelink or winnow until end of turn. (Damage dealt to it also causes its controller to lose that much life.)
Put the bottom card of your library into your hand.

Whenever one or more creatures you control attack, you may post a bounty on target creature. (Put a bounty counter on that creature. It has “When it dies, each opponent draws a card” as long as it has a bounty counter on it.)

Whenever Wild Dogs of the Night or another Horror enters the battlefield under your control, exile up to one target card in a graveyard. If that card was a creature card, you gain 2 life and put two +1/+1 counters on that Horror.

You may put a creature or planeswalker card from your hand onto the battlefield. It gains haste. Sacrifice it at the beginning of the next end step. Whenever an ability of that permanent is activated this turn, you may copy that ability. You may choose new targets for the copy.

Riot (This creature enters the battlefield with your choice of a +1/+1 counter or haste.)
Whenever Wild Lifescale attacks, proliferate. (Choose any number of permanents and/or players with counters on them, then give each another counter of each kind already there.)

Improve {G} ({G}: 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.)
If a +1/+1 counter would be put on a creature you control, you may put a deathtouch, reach, trample, or vigilance counter on it instead.

Surveil 1, then draw a card. (To surveil 1, look at the top card of your library. You may put that card into your graveyard.)
Create a tapped Treasure token.

At the beginning of each player's upkeep, you may exile target permanent that player controls. If you do, return that card to the battlefield under its owner's control at the beginning of the next end step.