I was running away from a mob of guys while on a horse on some medieval roleplay server.
There was some onplayertouch "lava" that I atempted to jump over with my horse... right as an icebow arrow hit my horse, making me fall in lava T_T
(for those who don't know, the icebow arrow turns the horse into a "frozen" man for some reason when you hit it, also casuing you to dismount.)