I'll always remember the werewolf from Andrew Spencer Studio's Ecstatica.
In all it's software rendered ellipsoid glory, the werewolf was the first monster you encountered in Ecstatica, and it was designed to be unkillable at this point in the game. I hadn't played resident evil by then, and the concept of "you should run from this encounter" hadn't entered my gaming lexicon yet. I was bewildered that I couldn't kill it, while all the time it could handily rip me apart.
Slowly I figured out how to escape from it, and realized running for my life was the solution to the puzzle. It was a rare gamer growth moment, where I re-evaluated what a game could be. It felt like the connection you get with an author sometimes, the crafted content hitting your every note perfectly.
When you do earn the wherewithall to murder the werewolf, its all the sweeter because of it's earlier dominance. Reflecting on it, It's sounds alien. Common sense today would dictate such a feature could route to a shelf moment, a casulty of a millimeter of non-obviousness. Makes me wonder what kept me put through the 20 load/save circuits I needed to dope out the winning strategy.
Anyway, I'm sure it's dosbox-able and worth checking out.