Prodigal Sorcerer
Tim is a nickname for the card Prodigal Sorcerer. The card got this nickname because it is a wizard that can damage objects on command, akin to the character Tim in the movie Monty Python and the Holy Grail, and the art in later printings was changed to make the homage more direct. Tim is also now used as a verb to describe the action of dealing one damage.
In its Alpha print, Prodigal Sorcerer's artist attribution is incorrect; on it, it reads that Douglas Schuler is the artist, but this is not the case - Douglas Shuler is the artist.
Formerly merely a Wizard, in Time Spiral, Prodigal Wizard was reprinted and its creature type was corrected to reflect the race and class system.
Planar Chaos
Prodigal Pyromancer introduced in Planar Chaos is a timeshifted version of the Prodigal Sorcerer. The card is more fitting in red and there was speculation at the time that it would be reprinted in a Core Set eventually.
This theory was confirmed when 10th Edition was released.