| 100% | LETHE | 5 | River of forgetfulness, in myth |
| 80% | LETHE | 5 | River of forgetfulness in Hades |
| 78% | LETHE | 5 | River of forgetfulness, in Hades |
| 70% | STYX | 4 | River of the underworld, in myth |
| 70% | STYX | 4 | River of the underworld, in Greek myth |
| 63% | LETHE | 5 | River in Alaska, "River of forgetfulness" |
| 61% | LETHE | 5 | River of forgetfulness |
| 58% | LETHE | 5 | Hades' river of forgetfulness |
| 58% | LETHE | 5 | Mythical river of forgetfulness |
| 57% | STYX | 4 | Underworld river of Greek myth |
| 57% | STYX | 4 | River of myth |
| 56% | STYX | 4 | River of Greek myth |
| 54% | MTETNA | 6 | In myth, home of the Cyclops |
| 53% | MIST | 4 | Symbol of forgetfulness in Ishiguro's "The Buried Giant" |
| 52% | LETHE | 5 | River of myth where one drinks to forget |
| 52% | ORESTES | 7 | In myth, killer of his own mother, Clytemnestra |
| 52% | NAIADS | 6 | River nymphs, in Greek myth |
| 52% | STYX | 4 | River in Greek myth |
| 51% | STENTOR | 7 | In myth, loser of a shouting match with Hermes |
| 51% | STYX | 4 | River bordering Hades, in myth |
| 51% | LETHEAN | 7 | Of a river in Hades |
| 51% | CONGO | 5 | River in “Heart of Darkness” |
| 50% | LETHE | 5 | River in Hades that causes forgetfulness |
| 50% | ARNO | 4 | River in Tuscany (anagram of "nora") |
| 49% | ANDUIN | 6 | Longest river of the Third Age in Middle-earth |
| 49% | ACHERON | 7 | River to the underworld, in Greek myth |
| 49% | LEANDER | 7 | In Greek myth, swimmer of the Hellespont |
| 49% | SIRION | 6 | Primary river of Beleriand in Tolkien legendarium |
| 49% | STYX | 4 | River in the fifth circle of hell |
| 49% | SWOLLEN | 7 | In danger of flooding, as a river |