Start by casting Paralysis. It almost always works against Mondo Mole. Fire works better on it than Freeze. Mondo Mole can put up a psychic shield, so stick to physical attacks while it is in effect.
You might need to just let Paula die because of how weak she is likely to be if you fight Mondo Mole right after rescuing Paula.
|Where it appears:||Lilliput Steps|
|PSI Fire:||50% effective|
|PSI Freeze:||25% effective|
|PSI Flash:||99% effective|
|Run away probability|
(add 10 after each turn)
|(Highest speed among Ness, Paula, Jeff, and Poo, subtracted by 19)%|
|Instant win against Mondo Mole||not possible|
|Probability that attack will miss||0%|