>>36440421Anon, when they go from concept to another for all future instances it's called a redesign.
Ivysaur is no longer "canonically" has only two leaves, it's no longer has roundy limbs, no longer has frog-like feet, etc..
Considering they were all done by Sugimori, he left the old Ivysaur and never used that design again, that's what called "re-design".
another example is Pikachu