Boggart Mob

Champion a Goblin (When this enters, sacrifice it unless you exile another Goblin you control. When this leaves the battlefield, that card returns to the battlefield.)
Whenever a Goblin you control deals combat damage to a player, you may create a 1/1 black Goblin Rogue creature token.

Frogtosser Banneret

Haste
Goblin spells and Rogue spells you cast cost {1} less to cast.

Bitterblossom

At the beginning of your upkeep, you lose 1 life and create a 1/1 black Faerie Rogue creature token with flying.

Earwig Squad

Prowl {2}{B} (You may cast this for its prowl cost if you dealt combat damage to a player this turn with a Goblin or Rogue.)
When Earwig Squad enters, if its prowl cost was paid, search target opponent's library for three cards and exile them. Then that player shuffles.

Boggart Birth Rite

Return target Goblin card from your graveyard to your hand.

Boggart Harbinger

When Boggart Harbinger enters, you may search your library for a Goblin card, reveal it, then shuffle and put that card on top.

Nath's Buffoon

Swamp

Boggart Loggers

Forestwalk (This creature can't be blocked as long as defending player controls a Forest.)
{2}{B}, Sacrifice Boggart Loggers: Destroy target Treefolk or Forest.

Warren Weirding

Target player sacrifices a creature of their choice. If a Goblin is sacrificed this way, that player creates two 1/1 black Goblin Rogue creature tokens, and those tokens gain haste until end of turn.

Prickly Boggart

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)

Cloak and Dagger

Equipped creature gets +2/+0 and has shroud. (It can't be the target of spells or abilities.)
Whenever a Rogue creature enters, you may attach Cloak and Dagger to it.
Equip {3}