ultrafantastic

The story

1. Proto-Indo-European*h₂el-
2. Latinūls
3. Latinultrā
4. Englishultra-
5. Proto-Indo-European*bʰeh₂-
6. Proto-Indo-European*bʰh₂nyéti
7. Proto-Hellenic*pʰáňňō
8. Ancient Greekφαίνω (phaínō)
9. Ancient Greekφαντάζω (phantázō)
10. Ancient Greekφανταστικός (phantastikós)
11. Late Latinphantasticus
12. Middle Frenchfantastique
13. Englishfantastic
14. English todayultrafantastic

From ultra- + fantastic.