Lask Frildur is an anthropomorphic monitor lizard and a secondary villain in the Redwall book, Pearls of Lutra.
Lask was a big, grey-scaled lizard who lived on Sampetra island and was the Monitor General under Emperor Ublaz Mad Eyes. Lask and his lizards served their master faithfully, acting as his shock troops against any opposition. Lask was the smartest and most competent of the monitors, and was thus Ublaz's right-hand. The Emperor sent Lask and ten of his lizards on a corsair ship to sail to Mossflower and find the coveted Tears of All Oceans pearls. The ship was captained by Romsca, a female ferret who hated Lask, so they were constantly at odds with each other, something which would culminate later on.
When they reached Mossflower, Lask and his lizards captured the Abbot of Redwall Abbey and held him as hostage for the pearls, which they thought were inside Redwall. The Abbey-dwellers didn't know anything about the pearls, so Lask had the Abbot taken back to Sampetra with them to remain a prisoner until they got the pearls. During the long voyage back, Lask and his monitors constantly harassed and tormented the weak Abbot, wanting to eat him, but Romsca defended him. Eventually the last straw came, and a battle broke out between the monitors and the corsair vermin, in which every single creature died. Romsca had slain Lask with a cutlass slash to the throat, but the monitor also fatally wounded her by shredding apart her back and neck.