3, 2, 1, Go...?

[beer is good for migraines]

I was playing in the training mode as Ky Kiske trying to do dead angle attacks, then there was a red special effect and the game said "3, 2, 1, Go!" and I want to know what caused this?

[Slaskburk]

You entered "Danger Time" state because two attacks happened to "clash", cancelling each other out. There's a small chance for this to happen any time two attacks clash.
During Danger Time you deal extra damage, and every starting hit is regarded as "Mortal Counter" (regardless if it was a counter hit or not) which enables stronger combos than usual. You can read more on Danger Time and "Clashes" here:
https://www.dustloop.com/wiki/index.php?title=GGXRD-R2/Movement#Danger_Time
https://www.dustloop.com/wiki/index.php?title=GGXRD-R2/Movement#Clashes

[beer is good for migraines]

Thank you!