Towers of Heaven Series by Cameron Milan

One day, six towers appear on Earth. Each one stands hundreds of stories tall, and are invulnerable to all attacks. At the base of each tower is a portal, welcoming in all who dare enter it. All sorts of magical monsters can be found inside the towers. Even treasure, magic and superhuman strength can be acquired. The problem is that the towers aren't a friendly place. Even worse, the towers sometimes release waves of monsters to attack Earth... moreOne day, six towers appear on Earth. Each one stands hundreds of stories tall, and are invulnerable to all attacks. At the base of each tower is a portal, welcoming in all who dare enter it. All sorts of magical monsters can be found inside the towers. Even treasure, magic and superhuman strength can be acquired. The problem is that the towers aren't a friendly place. Even worse, the towers sometimes release waves of monsters to attack Earth. In the year 2083, there are only a hundred survivors. In one last attempt, they challenge the final floor without regard for their lives. By some miracle, they manage to beat the floor at the cost of their lives, leaving only one survivor. As a reward for clearing the tower, he is granted one wish. He decides to go back in time to before the towers arrived. His goal is simple: prevent humanity from being wiped out. less

...Champion of Aros, God of Battle......Bearer of foreknowledge......A mythical third realm expert... Jason had it all, and yet he still couldn't prevent his father's death. He didn't even have time to grieve as his mission took precedence over all else. Pressing onward was the only path. But did he possess enough strength to clear the tower, even with Roy and Olivia at his back?The answer was obvious: only with humanity's best could he stand a fighting chance... more...Champion of Aros, God of Battle......Bearer of foreknowledge......A mythical third realm expert... Jason had it all, and yet he still couldn't prevent his father's death. He didn't even have time to grieve as his mission took precedence over all else. Pressing onward was the only path. But did he possess enough strength to clear the tower, even with Roy and Olivia at his back?The answer was obvious: only with humanity's best could he stand a fighting chance.Yet as his actions influenced the world, the more things changed. Worse, his secret identity, Index, was in the spotlight for releasing knowledge that couldn't possibly be known. If the major powers of the world found him, they'd no doubt use torture to obtain his secrets.A single mistake would cost everything.He already got a second chance.He won't get a third. less

Jason caught up to the current floor in record time, gaining powerful allies and unique skills along the way.But an unexpected change in the tower took away his greatest advantage.From now on, he's as blind as the rest.