msem-instigator

Enchant creature
When Strike Fear enters, draw a card.
When enchanted creature attacks, target creature can't block this turn.

Target creature gets +2/+0 and gains flying and first strike until end of turn.

Destroy target non-Assassin, non-Ninja, non-Rogue creature.

You may have Strikebreaker enter as a copy of a non-Aura enchantment you control, except it's a 2/2 Construct Actor creature in addition to its types.

Striptide deals 1 damage to target creature. Unattach all artifacts from it. It becomes red until end of turn.
Draw a card.

Create a Treasure token.
Showcase {2}{R} (Then if you cast this for its showcase cost, create a 1/1 red Bard creature token that can't block and exile this. Whenever it attacks, you may cast a free copy of this.)

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn.

Target creature gets +2/+1 and gains trample until end of turn. Create a tapped Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)

Bulwark — {2}{G}: Stronghold Recruit gets +2/+2 until end of turn. Activate only once each turn and only if you control a creature with toughness 4 or greater.

Flash
Enchant creature
Enchanted creature gets +1/+1 and has “Whenever this creature deals combat damage to an opponent, draw a card.”

Counter target noncreature spell unless its controller pays {1}.
If you control a creature with power 4 or greater, counter that spell instead.

Defender
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
{T}: Student of Lightning deals damage equal to its power to target player.

When Student of Secrets enters, fateseal 1. (Look at the top one cards of an opponent's library, then put any number on the bottom and the rest on top in any order.)

Prowess
Art of war — At the beginning of your end step, if Student of Shigure dealt damage to an opponent this turn, you may draw a card, then discard a card.

Whenever Student of Winds attacks, upgrade target attacking creature. (Give it one of the listed counters it doesn't already have.)
• +1/+1
• Flying

Whenever Student of the Coil attacks, target creature gains poisonous 1 until end of turn. (Whenever that creature deals combat damage to a player, that player gets a poison counter.)

When Student of the Crane enters, create a 1/1 white Bird creature token with flying.

{T}: Target creature you control gets +1/+1 until end of turn. Activate only as a sorcery.
Scavenge {W} ({W}, Exile this card from your graveyard: Put a number of +1/+1 counters equal to this card's power on target creature. Scavenge only as a sorcery.)

When Student of the Scroll enters, scry 2.

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.)
Whenever an Elf you control dies, you may search your library for a land card, reveal it, put it into your hand, then shuffle.

Until your next turn, target creature can't attack or block.
Fabled {1}{W} (Then if you cast this for its fabled cost, put it onto the battlefield transformed attached to that creature.)

If you've lost life this turn, you may cast this spell as though it had flash.
Return X target cards with different mana values from your graveyard to your hand. Put Studies Past on the bottom of its owner's library.

Investigate ten times. (Create ten colorless Clue artifact tokens with “{2}, Sacrifice this artifact: Draw a card.”)

Whenever Study Sphere or another artifact or enchantment you control enters, rouse 1. (Put a +1/+1 counter on a permanent you control. If it isn't a creature, tap it and it becomes a 0/0 creature in addition to its other types.)

Reveal the top four cards of your library. You may put one into your hand and the rest into your graveyard.
Compose (Then if you cast this from your hand, exile it and create a Saga token with “r3—You may cast a copy of this card from exile without paying its mana cost.”)