This game...was written for the Unexpanded VIC. It not only plays fast, but also improves typing skills.
Your mission in Typo Invaders is to protect the city of QWERT from the fatal alphabet bombs. As each letter drops, press the appropriate key before the bombs explode in the city.
VIC Typo Invaders was written by Kent S. Brewster and published as type-in source code in Compute! Issue 42, November 1983.