Board Thread:Bible Questions/@comment-28569169-20160708152222/@comment-31246436-20161004205458

True. However, the angel who unlocked the Abyss in not named so we cannot say with certainty who it is until it happens, if we even find out who that is. So it is best to not guess who it is unless there is other Biblical references that give additional information, even then it is best not to guess. John said the name of the king of the locusts was Abaddon/Apollyon, so it is best that we go with what he said. 
Although, considering John 10:10 (and interpreting the thief to be Satan), it might be possible that the "Destroyer" is Satan, since John 10:10 does say the thief comes to steal and kill and destroy, unless the thief is Abaddon and not Satan (although this is unlikely, Jesus was likely referring to Satan).