msem-instigator

Look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.
Tether (Then if you cast this from your hand, you may exile it tethered to a creature you control. When it dies, you may cast this from exile without paying its mana cost.)

({T}: Add {U}.)
As Seaside Grotto enters, you may pay 1 life. If you don't, Seaside Grotto enters tapped.
Basic lands you control have “{T}: Add {U}.”

Erratic (When this creature dies, reveal the top four cards of your library. Put a creature card that costs less than this revealed this way onto the battlefield and the rest on the bottom of your library in any order.)
Whenever a creature you control enters, if you didn't cast it from your hand, target land you control becomes a 7/1 red Elemental creature with trample and haste. It's still a land.

Whenever Lakeside Trickster becomes tapped, up to one target creature phases out. (Treat it and anything attached to it as though they don't exist until its controller's next turn.)

Haste
Menace (This creature can't be blocked except by two or more creatures.)
{4}{R}{R}: Ferocious Desert-Hunter gets +X/+0 until end of turn, where X is its power.

Nontoken creatures get -2/-2 until end of turn.
Fuse (You may cast one or both halves of this card from your hand.)

At the beginning of your upkeep, you gain 1 life for each color among permanents you control.
{W}{U}{B}{R}{G}, Sacrifice Sartha's Studies: Double your life total.

As Evil One's Mind Tricks enters choose Lafterii or Evil One.
• Lafterii — Wizards you control have “{3}{U}, {T}: Draw a card.”
• Evil One — Whenever a Zombie you control enters, target player mills two cards.

Flying
When Syrina, the Dragon Queen enters, gain control of target nonland permanent for as long as you control Syrina, the Dragon Queen.
{2}{U}: Exile Syrina, the Dragon Queen. Return her to the battlefield at the beginning of the next end step.

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.)
When Frontier Trackers dies, create a 1/1 green Elf creature token.

Flying
When Sweeper Drone enters, create a Function token with “Put a +1/+1 counter on each creature named Sweeper Drone you control.” (It's an enchantment. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)

Adorned — Commoners' Favored gets +2/+2 as long as it's equipped and/or enchanted.

{T}, Tap an untapped creature you control: Add one mana of any color.

Flying, haste

You may play an additional land this turn. Scry 1.

Flying
At the beginning of your upkeep, for each seven cards in your graveyard, Devotee of Winds explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then put the card back or put it into your graveyard.)

Prowess
{1}{U}, Tap an untapped Wizard you control: Target creature gets -3/-0 until end of turn.

Flying
If Warden of Distortion would die, you may exile a creature card from your graveyard. If you do, Warden of Distortion becomes a copy of that creature, except it's a 4/4 Nightmare Dragon and it has flying and this ability. It gains indestructible until end of turn.

Alpha (You may have this creature enter with a +1/+1 counter on it. If you do, it becomes alpha and can only attack alone.)
Brazen Chimera can't be blocked except by three or more creatures as long as it has a +1/+1 counter on it.

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

{T}: Add {C}.
{1}, {T}: Add {W}{B}.

Double strike
Art of war — At the beginning of your end step, if Jaakuna Tyrant dealt damage to an opponent this turn, put a +1/+1 counter on it.

Choose two —
• Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.
• Each opponent loses life equal to the number of cards you've drawn this turn.
• Rahstahde's Command deals damage to each creature equal to the number of cards you've drawn this turn.
• Create a 1/1 white Soldier creature token for each card you've drawn this turn.

Rhapsody {5}{W}{W} (Pay {5}{W}{W} to cast this as a 4/4, or as a sorcery to make it become a 4/4.)
When Kan's Faithful enters, exile up to one target nonland permanent with mana value X or less until Kan's Faithful leaves the battlefield, where X is Kan's Faithful's power.

Embellish {6}{U} (If you cast this spell for {6}{U}, create a 1/1 blue Thopter artifact creature token with flying when it enters.)
Whenever you attack, return any number of nonland permanents with different controllers and mana value less than or equal to the number of artifacts you control to their owners' hands.