KSP: "Your mom gets around so much she's in a highly eccentric orbit."

Your mom's so fat I can't even ultrahand her

--totk

The quantity of adipose tissue of your hive queen is of great interest and study of the enlightened species of the galaxy.

Renaming a Diamond Hoe in Minecraft

Skyrim: Your mother has aged so that her looks resemble that of a draugr

Fallout: Your mom's so old she looks like a feral ghoul

Your mum is so fat she is on A and B.

Yo momma so fat — she managed to tip the Iceberg.

(Club Penguin — though, it might've been obvious from my profile picture lol. It was just too easy.)

Oxygen Not Included: "your mum is like a shovel vole: round, with a dumb face, and always popping up everywhere uninvited"

“Are you going to make into the armada on time?”

… “depends on your Mom”

1. Yo momma so fat she alone could feed and clothe my colonists for an entire winter.

2. Yo momma so fat, not even Spitzer can pen.

Edit: added second one.

Yo momma so fat, when Kirby swallows her he gains the power of Diabetes.

Yo momma so stupid that she mines straight down.

Yo momma so fat that when she joined Foxhound they gave her the codename "Suffering Manatee"

Yo momma so stupid that she tames Rexes with Mejoberries.

Yo momma so stupid that she tames Raptors.

Yo momma so stupid that she misses Barrens Chat.

Yo Momma so stupid she preorders games.