724: Hell

There's also a Katamari level where everything is just slightly bigger than you, and a Mario level with a star just out of reach.

Explain XKCD: 724

942: Juggling

Later: 'Why is there a book hovering over the trash can?'

Explain XKCD: 942

1417: Seven

The days of the week are Monday, Arctic, Wellesley, Green, Electra, Synergize, and the Seventh Seal.

Explain XKCD: 1417

1250: Old Accounts

If you close an account while it's still friends with people, it contributes to database linkage accumulation slowdown, which is a major looming problem for web infrastructure and definitely not a thing I just made up.

Explain XKCD: 1250

1287: Puzzle

Prediction for Carlsen v. Anand: ... 25. Qb8+ Nxb8 26. Rd8# f6 27. "... dude." Qf5 28. "The game is over, dude." Qxg5 29. Rxe8 0-1 30. "Dude, your move can't be '0-1'. Don't write that down." [Black flips board]

Explain XKCD: 1287