I had a Resilient Skeezick in play, with the Subsume ability. When my opponent's Skywing Acidcraw used Acid Breath on the area Resilient was in, Resilient healed 10 HP. However, Subsume states that "When this unit is the target of an opponent's spell or non-basic attack ability, it is healed for 10 HP". This must be either a bug or a text inaccuracy.
I wonder, did he click directly on the Skeezick? For some reason, Cone/Bomb/Breath abilities seem to treat it as targeting any unit where you click, even though it is an AOE ability. I am pretty sure this isn't WAI.
Yup, this is when the cone is centered on the target. Im not 100% sure, since it is ages ago tha tI tested this (far before rvamp), but I believe it was even posssible to hit combat aware champions with cones by centering the cone on them.
When you target a champ with a cone even if it has combat awareness it will still take damage because it was single targeted. Same thing with subsume if you target the champ it will heal.
