9 printings of Congregate
They range from $0.14 to $0.40 — a 3× difference for a card with the same name. The set code and collector number printed along the bottom edge are what tell them apart.
| Commander Anthology | CMA 7 | $0.40 |
| The List | PLST M15-6 | $0.36 |
| Urza's Saga | USG 8 | $0.29 |
| Magic 2014 | M14 14 | $0.28 |
| Planechase | HOP 2 | $0.27 |
| Dominaria Remastered | DMR 4 | $0.21 |
| Masters 25 | A25 8 | $0.21 |
| Magic 2015 | M15 6 | $0.14 |
Not sure which one you are holding? OtterDex reads the set code and collector number off the card and tells you.