your dragon moved last round, please move a different piece
4-Player Free-For-All Infinite Bulldog Event Nuke Paint Capture the Flag Chess!!!

Was there an event that I forgot about when pieces could capture by moving through the piece that they captured?

SuperSam’s: It is now illegal to move the same piece two turns in a row.
Auk’s: Dragons were introduced, pawns can promote to dragons.
ry’s: Pieces can now “tank” other pieces, pieces may continue to slide upon capturing a piece, but cannot capture 2 pieces in 1 move.
It’s still your turn auk! I’ll be back late tonight.

OK, I will move pawnx(13,17) unless I can play TTxD since technically he stopped on my square and then kept moving so can't I turn back time and take his dragon.

No, but for example if the "En Passant Madness!" event were active that would be an option!
24. ChxP(13,7) ... DxCh(16,27) ... PxP(13,17)SuperSam to move.

Ouch x{ where one falls victim to this "tanking" event so does another!
25. DxTT(-10,12)Holo to move.
D×TT