msem-instigator

Haste
At the beginning of your end step, return Sunwatcher Aspirant to its owner's hand.

Sunwing has flying as long as it's your turn.

When Sunwright Scion enters, put a +1/+1 counter on each other creature you control.
At the beginning of each combat, you may have target creature with a +1/+1 counter on it gain your choice of vigilance, lifelink, or trample until end of turn.

Enchant creature
Enchanted creature gets +3/+3, has trample, and can only attack alone.

Whenever you cast a spell, harmonize. (Trigger up to one harmony of a permanent you control.)
Harmony — Target permanent you control becomes a 2/2 creature with flying in addition to its other types until end of turn.

As Superset enters, choose two abilities from among flying, first strike, lifelink, prowess, and vigilance.
Each creature you control with exactly one of the chosen abilities has the other chosen ability.

Whenever Supplanter of Realities attacks, proliferate. (You choose any number of permanents and/or players with counters on them, then give each another kind of a counter already there.)
Sacrifice another permanent: Supplanter of Realities gains indestructible until end of turn. Tap it.

Menagerie — When Supply Hauler enters, if there are five or more creature types among creatures you control, you may search your library for an artifact card, reveal it, put it into your hand, then shuffle.

Equipped creature has vigilance and “{T}: Add one mana of any color.”
Equip {1}

You may sacrifice three Treasures rather than pay this spell's mana cost.
Flying, trample, haste

Each creature with a law counter on it can't attack or block.
{2}{W}, {T}: Remove all law counters from all permanents, then put a law counter on target creature.

Whenever Supreme Mechanothurge or another artifact you control enters, up to one target artifact you control becomes a copy of another target artifact or creature you control, except it's an artifact in addition to its other types.

When Suraj Militant enters, target creature gets +1/+1 until end of turn.

{2/R}: Suraj Outrider gets +1/+0 until end of turn.

Identity — Sureshot Recruit has reach as long as you control at least two other creatures that share a creature type with it.

Prowess
Whenever you cast a noncreature spell, Surestrike Elite gains first strike until end of turn.

When this creature dies, if you control another Dwarf or Elf, draw a card.

Haste
Ward—Pay 3 life.
Whenever Surface Expeditioneer attacks, if it's embattled, it deals 2 damage to target player or planeswalker. (A creature is embattled if it has a counter on it or a permanent you control attached to it.)

Menace, reach
When Surfacing Horripede enters, surveil 2.

As Surge of the Fellors enters, choose Fellor or Lafterii.
• Fellor — Warriors you control have haste.
• Lafterii — Wizard creatures you control have “{2}{R}, {T}: This creature deals 1 damage to target player or planeswalker.”

Enchant creature
Enchanted creature has haste and first strike.

Whenever a creature you control becomes the target of a spell, that creature gets +3/+3 until end of turn.

You may have Surging Wurm assign its combat damage as though it weren't blocked.
Surging Wurm gets +2/+2 as long as seven or more cards are in your graveyard.

Flash
When Surreal Bakhtak enters, choose one —
• Destroy target tapped creature.
• Tap up to three target creatures.

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