i
Invent the new worst/most useless chess piece ever!

einstien hated chess

Also there's a gambit called the retarded pawn gambit:
That's the Latvian Gambit, I think.
latvian is e4 e5 nf3 f5
the pope:
is an AI, takes control of all 4 bishops and uses them to stop war (puts them in the worst squares for both players)

Francium
Element 87
Decays in 0.000000001 seconds turning the chess board, all the pieces, and the players into plasma.

The joker. The joker can be placed anywhere on the board. It can only move once before it is taken back off the board. It can only be used once for each player per game and can't attack any other pieces.
a piece called the joker already exists in bulldog chess
check it out in the chess960 and other variants section

A piece named Paap. It can be teleported to capture any piece on the board but It Only works in analysis boards. LOL

The Emo.
It sits in the corner, sobbing about how unfair the rules of chess are and how all the other pieces hate it.
The Rock(not rook)
ways
2000 pounds
there is a piece that is called a rock
yes