Gengar's a bit tough. Perhaps one way to make him more monsterish would be exaggerating the mouth somehow. Bigger teeth, longer length, different shape, etc. Or maybe instead of changing the mouth directly; a row of false fangs down his side and a thin cloud of fog billowing out of that area like a cape to ward off predators. Just shooting random ideas.

Still, it looks good especially considering the limited palette and lack of features on the original mon.

I am pretty impressed all the same. You transformed Gengar into something distinctively monstrous while still being recognisably Gengar. I never would have thought of giving Gengar that nose and snout. Gengar has this realistic look and anatomy despite the relatively low detail.

Oh, thank you! I had a Chiroptera vision for Gengar, hence why that nose/snout.

...OK, now I want to do more of these. ^^

Yes; bats eem to be a common choice in making mo realistic or animalistic Gengar.

I got that inspiration idea from my fav artist Arvalis

nice