Greetings Bettysue,

Thats an addon named: OhNoes
The screen where follow breaks flashes red 3 times, which i find usefull because you always notice that. When a screen (character) dies, you will have a red screen.
I always turn it off if i go to arena tho, because i see the things less good in red.

The skull in the end when i die i did manually tho, thats not the addon.

-Totemic