Ugh, okay I just discovered that playing as Riolu in Super Mystery Dungeon is like a secret “Hard Mode”. While playing as it, more powerful enemies appear and evolved pokemon are more common, but it makes you level up a bit faster, I havent leave the town and I am almost level 20.
Also, doing those missions about fighting another pokemon is BS, like that first one about fighting a lvl. 50 Salamance, where he normally has like 85HP after joining, but when you fight it, it have more than 300HP (I know it because I threw him like 3 blast seeds).