Tower opens up in the world, adventurers are selected randomly by magic forces to climb the tower in an RPG IRL setting with classes, gear, etc. People who enter the tower are free to leave but aren't allowed to speak about what's inside to outsiders so the contents of the tower are a mystery to normal people, except the main character who's sent a recording of himself beating the tower, which he studies to get perfect information once he's invited to the tower. Very generic plot premise and mission structure for the genre, right down to the missions being altered slightly to compensate for the MC doing everything perfectly. Arcs drag out way too long and the art is kinda weak IMO.
Adventurers inside the tower livestream their missions to other adventurers that climbed higher than them, the viewers can chat and interact with the streamers, including donating the tower's currency, so the adventurers have to appease their viewers. It's an interesting concept for a power fantasy story because a lot of readers do like seeing normal peoples' reactions to the OP MC, but I think the implementation is wasted potential. The MC has to act like he's just noob but the writing for his acting is pretty bad, and the story gets pretty repetitive with the pattern of MC pretends to not know what's going on -> Chatters are doubters or people laughing at the doubters -> MC does something no one else does -> Chatters spam "OMG/WTF"