The first break of the day: 1990 Topps Heads-Up! There were only 23 packs (box says 24), and based on the fact I had NO DUPLICATES, I can only assume Topps sold these such that one could buy a single box and get the whole set of 24 "cards."
Here are the results:
| Year, Brand, Set Name | Team Name | Player on card | Participant Name (or alias) |
| 1990 Topps Heads-Up | A's | Dennis Eckersley | Nathan |
| 1990 Topps Heads-Up | A's | Mark McGwire | Nathan |
| 1990 Topps Heads-Up | A's | Jose Canseco | Nathan |
| 1990 Topps Heads-Up | Angels | Jim Abbott | Group Pool |
| 1990 Topps Heads-Up | Astros | Craig Biggio | Dimwit |
| 1990 Topps Heads-Up | Brewers | Gary Sheffield | Group Pool |
| 1990 Topps Heads-Up | Cubs | Jerome Walton | Matt P |
| 1990 Topps Heads-Up | Cubs | Dwight Smith | Matt P |
| 1990 Topps Heads-Up | Cubs | Ryne Sandberg | Matt P |
| 1990 Topps Heads-Up | Giants | Will Clark | Matt R |
| 1990 Topps Heads-Up | Giants | Kevin Mitchell | Matt R |
| 1990 Topps Heads-Up | Mariners | Harold Reynolds | Ryan C |
| 1990 Topps Heads-Up | Mariners | Ken Griffey, Jr | Ryan C |
| 1990 Topps Heads-Up | Mets | Doc Gooden | Paul H |
| 1990 Topps Heads-Up | Orioles | Gregg Olson | Kevin B |
| 1990 Topps Heads-Up | Orioles | Craig Worthington | Kevin B |
| 1990 Topps Heads-Up | Padres | Tony Gwynn | Group Pool |
| 1990 Topps Heads-Up | Rangers | Rafael Palmeiro | Matt J |
| 1990 Topps Heads-Up | Reds | John Franco | Joe C |
| 1990 Topps Heads-Up | Royals | Bo Jackson | Matt F |
| 1990 Topps Heads-Up | Royals | Bret Saberhagen | Matt F |
| 1990 Topps Heads-Up | Twins | Kirby Puckett | Matt F |
| 1990 Topps Heads-Up | Yankees | Don Mattingly | Kevin M |