msem-instigator

This spell costs {2} less to cast if you sacrificed a Clue this turn.
Target player discards two cards.

Whenever you cast a spell with two or more black mana symbols in its mana cost, you draw a card and you lose 1 life.

Disgraced 5 (This enters with five -1/-1 counters. Whenever it deals combat damage to a player, remove all -1/-1 counters from it.)
Prevent all combat damage that would be dealt to Heir Unapparent.

Trample
Whenever Heir to the Old Bonds becomes the target of a spell or ability you control for the first time each turn, put a +1/+1 counter on it.

Create a token that's a copy of target creature you control.
Resurface 3 (You may cast this spell from your graveyard by tapping any number of untapped creatures you control with total power 3 or greater in addition to its other costs. Exile it as it resolves.)

At the beginning of combat on your turn, you may attach any number of Equipment you control to target creature you control.

When Heirloom Seeker enters, you may search your library for an Equipment card, reveal it, then shuffle and put that card on top of it.
Heirloom Seeker has first strike as long as it's equipped.

{T}, Pay 1 life: Add {U} or {R}.
{1}, {T}, Sacrifice Heist Headquarters: Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Colossal 5—{8}{W}{W} (You may cast this for its colossal cost to have it enter with five +1/+1 counters; or pay {8}{W}{W} as a sorcery: Put five +1/+1 counters on it if it has none.)
Ward {5}
When Hekaton Dismantler's colossal ability puts one or more counters on it, tap each creature you don't control. Those creatures don't untap during their controller's next 100 untap steps.

Flying
When Helar Ritualist enters or whenever you cast a spell, if {W}{B} was spent to cast it, each opponent loses 3 life and you gain 3 life. Put a +1/+1 counter on Helar Ritualist.

Flying, lifelink
When Helar's Herald dies, target opponent may give themselves two poison counters. If they do, return Helar's Herald to its owner's hand. Otherwise, return Helar's Herald to the battlefield tapped under its owner's control.

At the beginning of each combat, up to one target creature can't attack or block this turn.

Untap target creature. It gets +1/+3 until end of turn.

Tithe (As you cast this spell, you may tap three artifacts and/or creatures you control.)
Creatures you control gain indestructible until end of turn. If this spell's tithe was paid, put a +1/+1 counter on each creature you control.

During your turn, Helene is a 4/4 Human Warrior creature with hexproof and trample that's still a planeswalker. Prevent all damage that would be dealt to her during your turn.
[+1]: Create a green Stance enchantment token with “When a creature you control deals combat damage to an opponent, sacrifice this. If you do, draw a card.”
[–2]: Create a blue Stance enchantment token with “When an opponent casts a noncreature spell, sacrifice this. If you do, counter that spell.”

[+1]: Up to two target creatures you control each get +1/+1 and gain vigilance until end of turn.
[–3]: Create two 1/1 white Dwarf Peasant creature tokens. You gain 2 life.
[–7]: You get an emblem with “Creatures you control get +2/+2 and have double strike.”

When Helicos Aberration enters, forebode. (Create a tapped colorless Omen artifact token with “{T}, Discard a card, Sacrifice this artifact: Draw a card.”)

Trample
Resolute — At the beginning of combat on your turn, if Helicos Gargantua's power is greater than its base power, double its power until end of turn.

When Helicos Octopus enters, scry 1. If an opponent is cursed, scry 3 instead.

When Helicos-Drowned Captain enters, create a black Aura Curse enchantment token named Marked for Death attached to target player. The token has enchant player and “At the beginning of enchanted player's upkeep, that player loses 1 life.”

Enchant creature you control
When Heliod's Benefaction enters, scry 2.
Enchanted creature gets +1/+1 and has lifelink.

Whenever you scry, you gain life equal to the number of cards looked at while scrying this way.

Flying, lifelink, haste
At the beginning of the end step, sacrifice Helix Entity.

Choose five target cards in your graveyard. An opponent separates those cards into two piles. Put one pile into your hand and exile the other. Exile Hell or High Water.

Target opponent may have you draw X cards. If they don't, reveal the top X cards of your library. Hell's Verdict deals damage to that player equal to the total mana value of cards revealed this way.