While Diamond and Pearl introduced a lot of (pre)evolutions for older pokemon, quite a few of them were of pokemon that already had two or more forms.
There are still a bunch of One-Stage Pokemon that should get other forms...
I say we make a list of possible (pre)evolutions for those pokemon...
Any ideas for these?
Tauros & Miltank (They already can breed each other, why not a pre-evolution?)
Unown (Not likely, but possibly a pre-evolution that can become all the forms)
Plusle & Minun
Volbeat & Illumise
Lunatone & Solrock