You must reunite with Rasmus first to have a fair chance. However with very low STR is takes 3-4 rounds to get out of his swallow attack, That's practically a deathsentence. When i played the Boss with my Mage-Hero (INT+CHA) who only got 3 STR, 3 AGI and 5 END i needed to savescum a lot. When i played with my Warrior-Hero (STR+END) i only need the soup and a few MP Potions.