I think it would be interesting if there was a really powerful looking pokemon that evolved into a really weak looking pokemon.
Like others have stated, Pokemon like Pachurisu and Luvdisc need a new evolution stage. I also think it'd be kinda nice if the Shellos evolution chain gets a 3rd and final form (even though I think Gastrodon does fine being a Water/Ground type who's able to learn the TM's Earthquake and Avalanche, and also immune to Electric attacks). With the Dusk Stone being introduced in Generation IV, I can kinda see using it to evolve Eevee in a new Ghost-type Eevee-lution.
"He just put on 300,000 pounds....I'm SO jealous." Raven, Teen Titans
Have you heard of the saying "opening a can of whoop-ass"? I did that once in a dream.... I opened an aluminum can labled "whoop-ass" on somebody, and they disintegrated.
My favorite Bulbagarden smiley:
Umbreon is because the moon stone couldn't do that in gen 1 prior to umbreon's creation.
I still like these 2 ideas!! The first is about a brand new pokémon and the second about Luvdisc!
I've come up with loads.
Cublaze, the fire starter. A widdle lion with a fiery mohawk. Evolves into Cougurn, then Arslan, this beast looking lion with a flmaing mane, tail, and feet.
Tlelly, the water starter. A widdle elephant with a hose for a trunk. Evolves into Fantella, then Fanthorrent, a huge water-steel type elephant with battle armor, iron tusks, and a trunk like a cannon.
Vyppler, grass starter. Tiny snake with a seed pod for a head and a vine for a body. Evolves into Vypplorn, a beastly lizard with a woody head and a viney, muscular body. Evolves into Wyvorn, a grass/flying dragon with wings like Tropius, a thorny body, and a sick shell on its face.
And then, like, fifty more.
Vyppler sort of sounds like Bellsprout...but good ideas
but I'd say evolving at 12AM would be too difficult to do and too late for most people. and Dusk Stone's out of the question... I'd say if they make one, it'd be like you said, in a regional location thing.
Man the designers at Nintendo must read this thread!
Anyways, they could easily made it so that it evolved into Umbreon at night when using a Moon Stone. As day/night wasn't introduced back then, it could work. I always wondered why my Moon Stone and Sun Stone never worked on my Eevee though... (obviously, I found out later why)
If Eevee evolves into a Ghost-type by using a Dusk Stone at a special place (like a foggy area like other people proposed) then the problem is solved. It's like having the cake and eating it too!
And more, high-powered bugs. Scizor, Scyther, Heracross, Yanmega, Venomoth and Pinsir are all getting old. Something that actually makes me want to use a bug in-game (used Scizor on Platinum, other than that, none).