Glory – Use when defeating an enemy (Troll, Draugr, Kraken, or Monster). Gain 50% more Glory for defeating that enemy (rounded down). (e.g. Use when defeating a Monster worth 13 Glory; Gain 6 additional Glory.)
If I have already gotten this rune card , and want to use sacrifice tokens for defeating Epic Monster. Can I flip the rune card to get extra 50% glory from Epic Monster?
I think it can actually go the other way. The rulebook makes several references to "defeating" epic monsters. If you consider Epic Monsters as Enemies, then the argument can be made that you can use the rune here.