msem-instigator

{T}: Add one mana of any color.
{T}, Sacrifice Unicorn of the Vale: Add three mana of any one color.

Whenever Mahara Vanguard attacks, Soldiers you control get +1/+0 and gain menace until end of turn.

Flash
Flying
Prodigious Panya has base power and toughness 4/4 during extra turns.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Enchant creature
Enchanted creature gets +3/+3, has flying, and “{1}{W}: Put a +1/+1 counter on this creature.”

This spell costs {1} less to cast for each creature you attacked with this turn. (Those creatures don't have to still be on the battlefield.)
Flying

Riga's Workshop enters tapped.
When Riga's Workshop enters, you may mill two cards.
{T}: Add {U} or {R}.

This spell can't be countered.
Vigilance
Noncreature spells cost {1} more to cast.

Exile target creature you control, then return it to the battlefield under its owner's control. Create a token that's a copy of it. Those creatures gain haste until end of turn. Sacrifice the token at the beginning of the next end step.

Concord — Lurking Lahasia has first strike and lifelink as long as there are four or more card types among permanents you control.

{T}: Add one mana of any color.
{5}, {T}, Sacrifice Cosmic Chart: Search your library for a card, put it into your hand, then shuffle.

Destroy target nontoken artifact. Create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)

Flying
When Calamity Harbinger enters, it deals 4 damage to up to one target creature or planeswalker.

Menace
Foresight — Whenever you draw your second card each turn, target player loses 2 life and you gain 2 life.

Lost Station enters tapped.
{T}: Add {U}.
{U}{U}: Until end of turn, Lost Station becomes a 2/2 Horror creature with “This creature can't be blocked.” Activate only if you're horrific.

At the beginning of combat on your turn, Ruination's Hand gains flying until end of turn if a creature you control or a creature card in your graveyard has flying. The same is true for first strike, double strike, deathtouch, hexproof, haste, indestructible, lifelink, menace, reach, trample, and vigilance.

You may play an additional land on each of your turns.
{4}{U}{U}: Transform Misthollow Rites. Activate only as a sorcery.

Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
Mighty Xioshu can't be blocked by creatures with power 2 or less as long as you're in a renaissance.

Search your library for a basic land card, reveal it, put it into your hand, then shuffle. Mill three cards.

Danaj Sanctuary enters tapped.
Satrapies you control have “{T}: Add {G} or {U}.”

{T}: Add {C}.
Wanderlust — {T}: Add one mana of any color. Activate only if you control four or more differently named lands. If you control seven or more, you may add three mana of that color instead.

{G}, Tap an untapped Nymph you control: Overgrown Beast gets +2/+2 until end of turn.

Shuffle up to five target cards from your graveyard into your library. Reveal the top five cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other into your graveyard.

Whenever you attack, you may discard a card. If you do, exile the top two cards of your library. You may play one of them this turn.
Once each turn, when a card leaves your graveyard, you may add {C}{R}.