I need to get the polygon count down to around 20k, however some of the models have around 200k polygons. The decimate modifier works for reducing the poly count by about 50%, but anything more than that and the topology starts getting very screwed up. Here’s some before and after images for reference when using the decimate modifier to get the poly count form 200k to 20k:
Is there another way to accomplish this without losing this much detail?
Yes- manually retopologize to a low poly version and bake the details of the high poly version to a normal map for it. There isn’t really a “one click” solution like I think you’re looking for, it’s a process. If you’ve got the money, add-ons like Quad Remesher can help save you some time
Oh I see that makes sense. I haven’t messed around with creating my own normal maps yet but I found some good videos on it. I’ll give that a try. Thanks for the info!
Point here is, why do you want to reduce? Will it be a geame asset, will it be a background object in a movie? Do you simply want to increase performance?
If this question is answered, then you can think about how to reduce the geometry. Lowpoly + baking may not be neccessary under circumstances. For games, yes.
Here’s a technique using Shrinkwrap.
Sorry I didn’t see this reply. Yes it is for a game asset. I tried using the decimate modifier to get it down to 20k polygons and then baking the normal map, but it still looked quite bad. A few people mentioned manual retopology. Is that when you use a shrink wrap modifier and create a new mesh with fewer polygons over the old one, piece by piece? I haven’t tried that before, seems very tedious.
Yes, retopo can be tedious.
If it’s a game asset, the next question arises: Is it a hero object, visible in vlose ups or just a generic asset? For the latter, you might get away with very simple topology that is quickly modeled.
If you want a good hero asset, you have two options:
Try out tools like ZRemesher and the sorts and decimate afterwards or - for top quality - do it by hand.
There’s also a lot of other things to consider. Shading, a good cage, UVs and so on.
Usually you can only achieve that by manual retopo.
If you need more precise tips, just let me know. 
I guess the way to do it depends on the object, Remesh or Decimate are good for organic objects like trees or statues but not for manufactured objects, in that case you can first try some tools like Limited Dissolve or Un-Subdivide, or remove one edge out of two manually, which is not always so tedious, or retopologize with a brand new object that you’ll stick to the original (which I guess is the last resort, when the previous solutions can’t be used)
Thank you for the tips, much appreciated!
