flowey: freindship? HAHAHAHAH you realy are….IDIO-;sees rainbow comeing at him;….oh darn.

@Psycho Shy  
Part of it is probably colors. He’s really only got four: greens, greys, tans and the white of the monitor. Those colors are also all kept pretty much seperate. The green is all in the arms and shoulder-vine-things, the tan is all in the head and the grey is all in the machinery on top. With the ponies the colors are all over the place and tend to clash a bit. Plus they’re cluttered with tiny details. Just look at Rarity. Lots of tiny details on top of several distinct colors. Though Flowey is hardly undetailed he doesn’t have little details crammed into every inch of every surface. He has shading, yes, but not little designs all up and down his body.

The funny part is that Photoshop Flowey looks like a more cohesive design than the Rainbow Power ones.

@Stotter  
I would’ve thought they’d be less powerful, given ponies’ semi-magical nature and the general population’s vulnerability to those who intend to cause harm.

@Neko Majin C  
That’s what I was thinking.

Headcanon: Pony souls are more powerful than human souls. Not as wide a gap as monster and human, more like monster and boss monster or somewhere in between.

They actually have exactly the right amount of souls to turn Flowey into Omega Flowey. Just in time for someone else to fight him.

Getting a new power (which will never be used again after its introduction) fills you with determination.