Swadloon does evolve, but not by level, it is determined by happiness. When it has a happiness level of 220 or above. Happiness is determined by many factors, walking a certain number of steps and leveling a Pokemon up raises that level, and using bitter and nasty tasting herbs as well as fainting brings it down. If you would like to know more about happiness Bulbapedia has a very comprehensive article.
Swadloon evolves by happiness.
it evoves when it becomes a level 32
Level it up with its happiness value at 220
Sewaddle evolves at level 20 into Swadloon.
Sewaddle evolves into Swadloon at level 20. From there, it can evolve into Leavanny with max happiness.
Sewaddle evolves into Swadloon, which evolves into Leavanny.
Swadloon Evolves by Happiness
Swadloon evolves by happiness.
swadloon evolves into leavanny when you level it up with high friendship
Level 20 it evolves into Swadloon Then When It Is Super Happy It Evolves into Leavanny
sewaddle evolve when you level them up to lv 20 they evolve into swadloon
happens when is it happy
it's simple just
it evoves when it becomes a level 32
l 2 to the power of gorilla
Level it up with its happiness value at 220
Sewaddle evolves at level 20 into Swadloon.