Yeah that's an active Coldsnap, and Corvus still has Glaive Charges... that's really weird...Have you been seeing it in any other scenarios? Like do you take damage from Iceman's coldsnap? (I can't think of any other examples of Coldsnap damage...)
This is a bug that is costing many players precious units, potions, revives and actual cash. When is the fix coming and when is the compensation coming?
Corvus can take coldsnap damage if the enemy iceman is duped, ie he gets it at the start of the match. Since most enemy effects and your own activate at the same time, Corvus takes damage since the dot was applied before his Glaive charge went up. It's a design oversight