Can I get help looking for a certain manhwa?

So like ill get the basics first ----our guy the MC just like got back from serving the military and our MC here has a twin that went missing, and they have a terminally ill mother who died, our MC thought his twin ran away, but like got something (it's a text I think from the tower?)indicating his twin died trying to climb the tower to like get an miraculous medicine to heal their mother(the twin brother died bc he was betrayed by his team and like his girl(?)) And like the MC knows about this and gets mad(?) Wants revenge so he waits in like a park and waits for this door he gets in and climbs the tower guys I forgot the name I dunno other details