I suggest putting tons of melee damage and stamina into a lighting wyvern if you have one. Then go out and look for a deathworm which can only be found underground then agroed to come up and fight in the desert areas of Scorched Earth and Ragnorok. Dont worry if you dont have that high of a level wyvern. A 100 would be good and besides deathworms only spawn at level one or at least thats what i have noticed.Once you are ready, go to the Deathworm and kill it once that's fine
Doesn't anybody think that on dodo dex you should be able to see were the creatures live or are most common at? I've spent an entire day looking for a thyla and never found one. By the way I did even look in the red woods still didn't find one
Ragnarock - Go into ice cave and kill the weak deathworms there. Use a good shield to block their attacks and melee them with a sword, easy quick kills because they have so little health and they drop the same loot as a regular deathworm. Make sure to wear warm cloths.