Lets fix that.
The problem is probably that there is a desync between the server and the client and occasionally close targets aren't actually in front of you. The solution is remarkably simple: Just add another round AOE to those abilities (dawnbreaker, cleave, cresent sweep, etc.) with about 1m radius. Any target within that radius will also suffer the full effect of the skill. Of course if one AOE hits the other wouldn't be able to hit on the same target.
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