Predator Ooze Love the full green cost. Love the picture. Love indestructible.
The effect is a bit slow. Once you get him rolling though, he can easily surpass Leatherback Baloth in the long run He needs help. Without trample, he can be chump blocked (making him bigger for no reason). Without vigilance he leaves me open while he is trying to get bigger. Deathtouch would increase his growth rate significantly while destroying my opponent. And a lure effect would pull off the same growth as deathtouch albeit slower but would add a bit of control; espescially when combined with deathtouch.
Prey Upon works even better with Ooze when there's a Wild Defiance out, which helps you get a counter (in most cases) before you even attack, then swing, get another counter, so he is a 6/6 swinging, and a 3/3 normal p/t (possibly a 4/4 if they block and die). Trample is key though. Rancor would be ideal. Also Revenge of the Hunted gives trample, a huge power boost, and lure...