Nice start !
My only thought is that I would probably give the TRex more weight...
I mean, It was a huge Dinosaurus and he seems too slim for me.
Great start anyway.
Hahaha, that made me laugh, funny concept.
It's not a T-Rex, it's a lizard, that's why he needs a spear! ROFL
A lot of work is needed to pull this off, but for a quick rough of where your trying to go, it's not bad and very 'Frazetta' in the undertaking.