Do you think Witchaven(1995) was unfairly treated when it first came out?
Critics ignored it's many innovations(first FPS with RPG elements, first FPS to focus on melee battle, first FPS to allow 16 players at the same time, etc.) and just called it a Doom clone. If you haven't played it, it's free at www.abandonia.com .
I thought HeXen was the first FPSRPG to be released, guess I'm wrong. But if critics call this a DooM clone, they're right to some extent. But the thing is, there were few games that could could be original. It's like calling Pong a rip-off of Pong on another console because it's exactly the same sport.
But that's surprising though - how can they hate 16 players in one game? Plus a huge focus on melee, which would've been a major change to most games. I'll have to give it a try!