For whatever reason a lot of the best ones (imo) are platformers.
I have tried and can personally reccomend the following:
Viotoxica. Is my personal favorite, the transitions to the animations can be rough, but the actual gameplay is good and the focus is 100% Vore.
Lillians Adventure. It's not
entirely Vore but has a goodly bit of it.
Echidna Wars. It's pixel art and BRUTALLY difficult, but is entirely Vore focused and has some really good animations.
As for non-platformers, it gets a goodly bit harder to find anything with any real teeth to it. (hehe)
Super Fatty RPG. It's rough in the artstyle and the gameplay, and it's focus is a lot more on Feedism/Weight Gain, but it does have a heavy Vore element. Not the greatest, but by FAR not the worst thing I've tried.
Churn Vector. Is a 3D stealth game, and surprisingly not terrible. It only does Cock Vore though, so if that's not what you're after skip it.
Vessel Tactics. Is delightful, something rather like Disgaea. It is sadly in a very early state at the moment, and updates are inconsistent/rare at best across all the devs games.
The Adventure of Monster Tamer. Seems pretty much entirely Vore. Haven't actually played this one yet so can't help you on content or quality.
Then there's always the super content dense text-based games like
TiTS,
CoC, and I'll toss
FoXXX in there as well, for containing SOME amount of vore, though you're gonna need to go looking for it.
Very lastly because I cannot seem to find anything about the actual quality of the games in question and my backlog is too great at the moment, both Voronica Games,
Voronica Cleans House, and
Voronica Goes to Town, are rather obiously Vore based, but beyond that I know effectively nothing.
Hope that helps, if you have more detailed requirements there's probably something I missed somewhere.