You'll need to make it have high happiness/friendship during the day to make it evolve into Roselia.
mightyena doesn't evolve on Pokemon pearl, he doesn't evolve in any Pokemon game!
Buizel evolve at level 26.
evolve snowver at level 40
IT DOESN'T EVOLVE
level 30.
at level 30
Level 18
level 50
Level 20.
at level 14
Level 37
Level 20