Well after i watched Lucky one and Monster mv i was like "damn.. the maze", "wow! the intro dance (Monster mv) looks like the one in wolf mv", "the white watch? damn baby", "ah~ that look Biki (baekhyun) give to Lay~",  "ohh~ it was Biki (baekhyun) who save them all.. i see", "those guys are hurting". Soooo, i make my own theories~

the maze represent Overdose which it reminds us of Kris and Luhan. They stuck in Overdose era. It also means that it was the last time Exo stand as OT12. The maze is in Lucky one mv and not in Monster bcuz when Kris and Luhan leaving Exo, they left without any bad injury like Tao had.

the intro dance in Monster mv.... it looks like the ending dance in Wolf mv. Remember when it used to be Sehun and Luhan who did the dance? now it was replaced by Kai. Before Sekai exist, it was HunHan in the beginning.

the white watch. Watch = Time. it means Tao. Exo's time control. Why the watch is in Monster mv and not in Lucky one mv? well when Tao left Exo he was injured so bad so ofc he's not the Lucky one.

the look Biki give to Lay.. well Lay is the only chinese left in the group so it was like Biki is begging him to stay with them.

don't you wonder why Biki is the one who save them all? why not Suho? the leader? that's because Byun Baekhyun knows everything than the other members. well that's what i think. But you see, he had suffered enough. Remember when he got slapped just because he still want to be close with Kris? even though Kris already left him and the others? Remember when he apologize for his relationship with his dream girl (taeyeon) ? even though it's not his fault tbh. This Biki guy, sometimes he looks funny and stupid but deep inside he knows everything what's going on around him.

Exo are hurting in the mv. This shows us that they are hurting from all the pain Sm have caused them. You know what i mean right ? and they are rioting in the mv against the netizens who keep on bringing the only chinese member left in the group. Yeah some netizens want Lay to leave the group and the other members struggling so hard to keep him stay in Exo.  

So yeah this is just my made-up bull which i can't prove it. Till when? Only time will tell.

Don't take it seriously juseyo ^^

All the best EXO!

See you again next time boys~

oh! ignore my grammar mistake juseyo cuz english is not my main language ^^