User blog comment:Blademaster00/Official Amatsumagatsuchi Talk Page/@comment-203.82.94.82-20110131073809/@comment-3298463-20110131142300

MHP3rd has Royal Ludroth. It doesn't have underwater areas presumably because it would be too hard to control your character with only one pad.

Lagiacrus was most likely left out because in land he moved too similarly to Agnaktor and RL, and unlike them there's nothing really special he can do while in land (RL is a begginer monster, while Agnaktor has the Heat Beam, digging, armor, etc.). Gobul is just a pushover on land. Hapurubokka is somewat similar.