It would be to level up all skills to max in one day without mastery, it can be any day but you have to level all at once without gaining xp in any way before that day, that would mean that the only way would be gaining money with actions that give no xp like tilling and artifact spots so clay farming... Yes it would be tedious but and yes you would need rng if the world isn't on legacy mode cuz maybe the only way would be books, but c´mon it isn't lie no one would like the challenge??