msem-instigator

Enchant creature
When Warrior's Discipline enters, put a +1/+1 counter on enchanted creature.
Whenever enchanted creature deals combat damage to a player, double the number of +1/+1 counters on it.

Creatures you control get +1/+0 and attack each turn if able.
As long as you control four or more Mountains, attacking creatures you control get an additional +1/+0 and have first strike.

You may put a Dragon creature card from your hand onto the battlefield. That creature gains haste until end of turn. Return it to its owner's hand at the beginning of the next end step.

Trample, prowess
You may exert Wartorn Veteran as it attacks. When you do, double its power until end of turn. (An exerted creature won't untap during your next untap step.)

Haste
When Wasteland Rabblerousers enters, creatures your opponents control with power X or less can't block this turn, where X is the number of Deserts you control.

First strike
Wither (This deals damage to creatures in the form of -1/-1 counters.)

Advance {3} (Cast this for {3} to advance it as it enters. {3}: Advance this as a sorcery.)
Whenever Wastes Scrambler advances, put your choice of a +1/+1, first strike, menace, trample, or vigilance counter on it. If {R}{W}{B} was spent to advance it, repeat this process twice.
Crew 1

Trample, haste
Defiance (Whenever this creature takes damage, if it survives and wasn't defiant, put a +1/+1 counter on it and it becomes defiant.)
Whenever Wastewolf attacks, it deals 1 damage to any other target.

Flying
Whenever a nontoken, noncreature, nonland permanent you control enters, create a token that's a copy of that permanent except it has no mana cost and it isn't legendary.

Whenever Watchkeeper Deserter attacks, discard up to two cards, then draw that many cards. Watchkeeper Deserter gets +X/+0 until end of turn, where X is the total mana value of the discarded cards.

Remove all -1/-1 counters from target creature. That creature gets +3/+3 and gains trample until end of turn.

Watchkeeper's Retort deals 2 damage to target creature or planeswalker. Scry 1. (To scry 1, look at the top card of your library. You may put that card on the bottom of your library.)

As an additional cost to cast this spell, discard a card.
Create three 1/1 red Soldier creature tokens with haste.

Waterfront Market enters tapped unless you control a basic land.
{T}: Add {W} or {U}.

Prowess
Whenever you cast a noncreature spell, target creature can't block this turn.

When Wavebreaker enters, add two mana of any one color. You can't spend this mana to cast spells.

Pressure {3}{G} (You may cast this spell for its pressure cost if seven or more cards are in your graveyard.)
Put two +1/+1 counters on target creature you control if Way of the Danithra was cast for its pressure cost. Then it fights up to one target creature you don't control.

Exile all Inscription cards from your graveyard and all exiled Inscription cards you own. For each card exiled this way, you may inscribe it onto a creature you control. (Whenever that creature attacks, its controller may cast a copy of the inscribed card without paying its mana cost.)

Equipped creature gets +2/+2 and has vigilance.
Equip {4}
Wanderlust — Wayfarer's Adornments has equip {0} as long as you control four or more differently named lands.

{1}, Sacrifice Wayfarer's Amulet: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.
{3}, Sacrifice Wayfarer's Amulet: Search your library for a riddle card, reveal it, put it into your hand, then shuffle.

{T}: Untap target basic land.

{T}, Pay 1 life, Sacrifice Wayfarer's Shrine: Search your library for a basic land card, put it onto the battlefield, then shuffle.

Survivors you control have double strike.

When Wayfaring Realmstitcher enters, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle.