Quality of Wakfu was always kinda shaky, S1 had a few bangers and a lot of stinkers, but managed to hit the right notes when it counted so it got a pass.
I have no idea why anyone liked S2, it was horribly mediocre, the villain had no real charm, and the finale was a clusterfuck of retarded powerups and bad fanservice.
S2.5 was pretty decent, except Adamai's characterization gets more and more insufferable for no discernable reason.
S3 was just agonizingly bad, bad plot, bad fights, bad characterization, absolutely awful drama and a conclusion that makes no fucking sense.
So, overall, I would say 50/50, but even in it's best moments it's already 50/50, so it's more like 25/75. A few great moments in a sea of derivative and unfunny shit.