Lore Seeker

All Rats have fear.
{T}, Sacrifice a Rat: Create X 1/1 black Rat creature tokens, where X is the number of Rats you control.

Swarm of Rats's power is equal to the number of Rats you control.

Black creatures get +2/+0 until end of turn.

Ninjutsu {B}
Whenever Skullsnatcher deals combat damage to a player, exile up to two target cards from that player's graveyard.

When Chittering Rats enters the battlefield, target opponent puts a card from their hand on top of their library.

Target creature gets -2/-2 until end of turn.
Flashback—{1}{B}, Pay 3 life.

{B}, Discard a card: Regenerate Dirty Wererat.
Threshold — As long as seven or more cards are in your graveyard, Dirty Wererat gets +2/+2 and can't block.

Draw four cards. You lose half your life, rounded up.

Swarm of Rats's power is equal to the number of Rats you control.

Destroy target nonblack creature. It can't be regenerated. You gain life equal to its toughness.

Destroy target nonblack creature. It can't be regenerated. You gain life equal to its toughness.

Fear
Nezumi Cutthroat can't block.

All creatures gain fear until end of turn.
Cycling {1}{B}
When you cycle Dirge of Dread, you may have target creature gain fear until end of turn.

When Chittering Rats enters the battlefield, target opponent puts a card from their hand on top of their library.

Rat offering
Whenever a permanent is put into an opponent's graveyard, that player loses 1 life.