Assembled Ensemble

Vigilance
Assembled Ensemble's power is equal to the number of Robots you control.
Whenever you cast a spell with an artifact creature in its art, create a 1/1 white Clown Robot artifact creature token.

Spooky Clown Mox

{TK}{TK} — Vigilance
{TK}{TK}{TK}{TK} — {1}, {T}: Tap target creature.
{TK}{TK} — 1/5
{TK}{TK}{TK} — 5/4

Clown Extruder

Visit — Create a 1/1 white Clown Robot artifact creature token.

Pietra, Crafter of Clowns

Haste
Robots you control get +1/+1.
{R}{W}, {T}, Tell a joke you haven't told this game to someone outside the game: Create a 1/1 white Clown Robot artifact creature token. If that person laughed, the token gains haste until end of turn.

Clown Car

When Clown Car enters, roll X six-sided dice. For each odd result, create a 1/1 white Clown Robot artifact creature token. For each even result, put a +1/+1 counter on Clown Car.
Crew 2

Vicious Clown

Whenever another creature you control with power 2 or less enters, Vicious Clown gets +2/+0 until end of turn.

Clowning Around

Create two 1/1 white Clown Robot artifact creature tokens, then roll a six-sided die. If the result is equal to or less than the number of Robots you control, create a 1/1 white Clown Robot artifact creature token.