Does anyone know if I can stain deer antlers using wood stain? I recently had my 8 point fixed it needed about a 4 inch tip and the taxidermist did not do a great job of making his putty match the color of my rack, and I want to make it all match and a little darker before I put it on a nice plaque. Thanks for any help.

yes you can ; sometimes shoe polish work good also.

Depending on what was used, there's a good chance that it will not acept stain. Most common epoxies will not. You may try some light coats of artist paint wiped on with a paper towel. You may or may not get what you want, but it's worth a shot. Lightly buff it with some very fine steel wool afterward.

But will real deer antlers accept wood stain or varnish

Yes, real antler will accept stain just fine.