Geonosian Arena Monsters Vs. Rancor and Wampa

Reeks aren't big enough. The rancor has faced two charging banthas before (Tales from Jabba's Palace) and come out relatively unscathed. Rancor takes this by itself, again.

It's made easier if the wampa goes after the Nexu, which is a battle it can and will win.

Haven't you seen the movie? The Reek is big enough and would really crush bones with his head.
The Rancors body isn't build strong enough. And the ROTJ one is small.

Originally posted by Ballister
Fine, you want support? Wampa dies with one (or 3, I forget) slash.

It actually lives thank you very much. It leads a band of Wampas against Luke later on in a novel during the most small-worlded and stupid encounter ever.

Compare the size of a reek with the size of a bantha, overlord.

Banthas are built twice as big, and the ROTJ rancor took on two of them as well as Tusken riders at once. The reek will be child's play in comparison.