I built Tictactoe in Excel by creating every possible board state and then hyperlinking between them. I fixed the window size to 3x3 so the window would scroll to each state. Later learned AppleScript to automate parts of this process and eventually got in to HTML.
Same here! I had a basic game where an enemy moved across the screen towards the character and you had to shoot it. Clicking the enemy would hyperlink to a slide where you shoot the enemy, the enemies animation finishing (when it touches the character) would link to a slide where you died. Working out how to do conditional logic in PowerPoint at 11 opened up a lot of exciting ideas for PowerPoint games for me. Though it lead to a lot of slides…