You need to play more aggressively against low-rateds in fiesta. Develop the knight early, so you can trade for bishop. Prioritize rooks pawn over other pawns, and attack hanging pieces when you can, since they may not see. You missed out on all three of these in this game. As for the worst games forum, you're welcome to make one yourself lol
And this is why I refrain from playing Open Fiesta Arenas
https://www.chess.com/4-player-chess?g=6617025
It's like someone has a bounty on me...
Can someone make a worst games forum?