You have to locate the river and drink from it, therefore increasing your strength. The river is at the centre of a cavern, which is guarded by trolls.
Notes
Part of the Runemagic series, an Eamon-like system in which a character was created in a separate program and could be taken from one adventure to another. Eight adventures in the series were planned; only two were released.
Versions for the ZX Spectrum, Electron and Commodore 64 were advertising as coming soon but don't seem to have been produced.