While I appreciate the flashback
Infinitron , I am also disappoint.
ANYONE trying to be serious in/about gaming should know about the Freescape engine. It is, just like you said, the first engine that allowed true 3D.
In a very basic manner.
I mean, the engine was coded on an Amstrad CPC, what did people expect? It can't cope with massive changes to the player's X,Y,Z position in real-time, note in the video when the player 'falls' into the pool (around the 5:20 mark), the screen goes black while the engine computes the player's new position.
The monsters floating around? That's not one moving polygonal object, that's
several polygonal objects that appear/disappear in a set pattern, like lights on a light fixture.
Ultima Underworld (and Wolf3D) got so much attention because they updated themselves in real-time, something the Freescape engine could only do in a very limited capacity.
(On that note, I'm pretty certain that there's a 3D game on the Amiga/Atari ST that could do "true 3d" in real-time before Ultima Underworld. Possible suspects would be Midwinter/Midwinter 2, The Mercenary series (Mercenary/Damocles/Mercenary 3) and possibly even games like Interphase and Cybercon 3. Of the aforementioned games I only played the Midwinter games, but it's been so long I can't remember precisely whether it was "true 3D" or only 2.5-dimensional.)
But watching that Castle Master video brought back some memories, I played (and completed) that game back when it was new, and I still remember so many things from it:
# It was one of the first games to cater to both genders. You can be the guy saving the girlfriend, or the girl saving the boyfriend. It didn't really matter for the gameplay itself, but it's a nice touch for a 1990 game.
# Having to go 'round back' to find a vital part of the game was a common trope in Freescape games. A lesson that comes in VERY HANDY when playing Thief, for example.
# Underneath the castle is a labyrinth of caves, full of monsters and identical-looking passages. There are several ways to get in there, one of them being underneath that boulder you see right outside the castle. Another entrance is under the rug in the wizard's hut, one through the well IIRC and one either behind the pulpit in the chapel, or underneath the altar. There was only ever one way out, however. Can't remember where that was.
# Some monsters (Igor, for example) were immobile, but the player had to shoot certain parts of them in order to kill them, and all before the player's strength was all sapped away.
# IIRC you could walk through the fireplace in the kitchen to reach a backroom.
# In order to move heavy objects, the character needed to be strong enough. The player's strength is represented by the weights on the barbells, and it's boosted by all that cheese lying around.
# To get on top of the chapel (which was vital) one had to stand on the drawbridge before shooting the button that opens/closes it.
# The horse in the stable had a hole on its underside which contained something vital.
# Besides having to hunt for a fuckload of keys, I faintly recall something about needing to collect 7 "tokens" of some sort in order to beat the game, and that at least one of those tokens was in the caverns beneath the castle.
# What I found to be the most fascinating thing about Castle Master, however, was its sequel. Castle Master 2: The Crypt, tells the story of the player AFTER he dies in Castle Master, and is trying to escape the afterlife and return to the land of the living. It was conceived as something that the player would have to complete to be returned to life and be allowed to try playing Castle Master again. While there's no in-game connection between the two games, the CM2 manual states this very clearly. It would have been interesting to force the player to complete a (mini)game before being allowed to play another game of Castle Master. This also beats Prey's "mini-game after death" by about 16 years.