Mind Freeze can be very useful when playing against casters. See Tips and tactics for information on using interrupts.
This ability was mentioned in the April Fools' Day patch 6.1.4 Evil Patch Notes: "Mind Freeze now renders the target unconscious and causes them to slowly turn to ice, unless you erase their memory of the incident and spend the rest of your life in seclusion." This is a reference to the movie Frozen.
Patches and hotfixes
Patch 9.0.1(2020-10-13): Now learned at level 7 (was 62).
Patch 7.0.3(2016-07-19): Now learned at level 62 (was 57). Range increased to 15 yards (was melee range). Spell lockout duration reduced to 3 seconds (was 4 seconds).
Patch 5.0.4(2012-08-28): No longer costs Runic Power (previously cost 20 Runic Power). Cooldown increased to 15 seconds (was 10).