I've seen a few mentions of this in the "what was bad about Amiga" thread - regarding the fact that Amiga joysticks only have one button.
Now, my joystick broke the other week, and I had a friend send me a pad from a megadrive, which is compatible as you probably know. Out of A, B and C, button 'B' functions as the Amiga's fire button.
Played Turrican 1 last night, and accidently hit button C. It triggered the screen clear bomb! And the crouch + C triggered turning into a cog. How was this game clever enough to have multibutton support, when it was unheard of back then?
p.s. I'll report back with any other games that support button C