Tower of God/WMG

Baam was created by Enryu
It is rumoured that Enryu is capable of creating life out of Shinsoo. If this is true, he could have used Shinsoo to create Baam who seemingly has no parents and has been alone his whole life.

No one has actually reached the top of the tower yet.

 * The current king simply stopped at the 134th floor, and declares everyone who reaches the same point to be a victor and a Ranker, granting them power in exchange for their agreeing not to challenge the status quo. This is why so many people are concerned with either weeding out people who might upset the balance of power in the tower, or with encouraging them -- the current king and the entire establishment of Rankers is actually working to prevent anyone from ever reaching the top, and a sufficiently powerful Determinator could break the whole system by forcing the issue. This also explains why none of the Rankers we've seen really seem that fulfilled. And when Baam asks one of the Rankers what's up there, their response is extremely evasive.
 * This has been all-but-stated explicitly, really. The king only reached the 134th floor, and nobody has cleared the 135th floor. When most people talk about the 'top' when it comes to Rankers and the like, they seem to simply mean the currently-highest-conquered floor of the tower. But, by implication, the great rewards supposedly at the 'real' top of the tower have never been claimed by anyone.

There are no rewards for reaching the top of the tower.

 * Building on the above. If nobody has ever reached the top of the tower, how do they know what's up there? The truth could be a lot less amazing than the legends make it out to be, or it could be a "the journey is important" thing. Or they could have to beat up god for being such a jerk and setting up the tower in the first place.

The tower has no top; it just goes on forever.

 * You're never supposed to stop pursuing a distant, unreachable dream. The king and all the existing Rankers (the ones we've seen, at least) failed by stopping and sitting on their laurels lording over others with their power; you're supposed to just keep climbing the tower forever. The two top-ranked Rankers have disappeared because they're still ascending.

The tower is the same one from Makai Toshi Sa Ga.

 * The similarities are so close that it's hard to avoid thinking that it was an inspiration, at least (huge divine tower at the center of the universe extends up into the sky, with an entire world on each floor; an overlord has taken over the tower and appointed rulers for each layer.)

Akryung is Urek Mazino.

 * Several panels suggest that Akryung is an irregular, yet no one seems concerned about him the way they are with Baam, Yuri doesn't find him interesting, nobody's worried about him disrupting the tower, etc, even though he seems on the face of it to be drastically more powerful than Baam. Nobody noticed him enter, even though Baam's entrance seems to have attracted massive attention. Both Androssi and Yu Han-Sung seem to know him; Androssi's knowing him shouldn't be possible according to the rules of the test, since he was in her group. The only logical way Akryung could be an Irregular, freakishly powerful, and someone known to both of them without alarming them is if he were an Irregular who was already known in the tower -- and the only active irregular is Urek Mazino.

Akryung is Enryu.

 * Most of the logic of the above WMG holds for this one, too, though this one assumes that Enryu came back and that those who recognize him keep quiet about it. Enryu is specifically noted as having a red motif, being an excellent spear-carrier, and using huge red spears specifically, which fits Akryung's methods and appearance fairly closely.

At some point, somebody will shoot a beam from his crotch.

 * Simply because it would be the most hilarious and longwinding Brick Joke ever and "not even Urek has that kind of Bullshit ability!"