First appearances of game mechanics

Hey,

Just curious to know about first appearances of a couple game mechanics and maybe some back-story as to how they came about. Specifically I was looking at:

• The first appearance of loading screen advice prompts e.g Borderlands class and skill hints.
• The first appearance of dialogue tree options where the success % was linked to a character stat (ususally charisma or persuasion) such as in Kingdoms of Amalur: Reckoning.

Tried searching through Google and Wikipedia for a few hours but wasn't able to get a discernible answer. Would also be interested to hear of any other first appearances of game mechanics and back-story anyone else might know about.

Any help would be much appreciated.

The oldest game listed on the Loading Screen Advice page is Moonstone: A Hard Days Knight, which I have never heard of before.

I don't know about the second. The earliest I know of for character stat driven dialogue success is Fallout, but that might not be the first.