Ascension Revives the fallen [bug]

I have no video proof of this or any screenshots, but apparently if Kog maw dies, moving in his passive he can still pickup the "ascension Obtainable" and getting acsended, we thought he would end up dieng but he was back alive. im not sure if this is a bug, but its rather unfair considering that we where in the circle aswell. blocking the ascension for our enemys, however kogmaw still got acended. it happend twice that game. im pretty sure it also works with karthus or maybe zac.