One vital thought I had in mind when allocating these points, was to take into account the 'core' of these older RPGs, and how it's changed from later, more robust RPGs. A large majority of the games listed are just battle simulators using a detailed (and often slow-paced) combat system. Basic concepts such as dialogue, branching plotlines and multiple pathways through the games that we take for granted today simply weren't available, except in very basic terms. Even re-playing the game with different builds is not accepted for many of these games, the focus is on having the player build the perfect party of adventurers to reach the end of the game.
With that said, I also take into account games that are fun to play, raised the bar or are generally notable in the field of RPGs (or gaming as a whole).
Finally, I object to only 10 points being allowed, with all these restrictions in place. More would be needed to do this proper justice.
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My 10 points, in chronological order:
# 3 points to Ultima 4: Quest for the Avatar, for daring to buck the trend. Instead of the player raising a party of murderhobos in strength so that they can take down the Big Bad, the player must instead grow his character to become a better person, so that he can help the game world deal with its socio-spiritual problems.
# 3 points to Eye of the Beholder (1), for providing a good all-round approachable RPG experience and being very free-form in its design. Almost every party build has a chance of success, and there are multiple paths available in traversing the dungeon.
# 4 points to Ultima Underworld: The Stygian Abyss, for daring to be. It didn't just raise the bar, it redefined it along the way, setting new standards for the years ahead.