The cards are for if an effect stays out like "MMind gets +2 power", then we like to have some sort of visual to remind us.
I use a d10 set to the appropriate fight for the killbots in that scenario. It starts with the 3 up and increases as each twist is drawn.
I figure could use a d10 or d20 to show any increased power of the Mastermind.
Great ideas for making the game more difficult though.