This cache is designed to be done by high clearance 4WD which makes the experience.
Approaching from Chettle Road, you'd see a steep rocky hill. Go up that. It's fun 
From there it is a shortish drive through Wombat forest. Expect some muddy tracks and a bit of slipping and sliding.
Do not attempt this in 2WD - you'll get stuck. Be sensible and have recovery gear with you. If your not confident, hike it or leave it be. There is a big difference between fun and sliding off an embankment.
I didn't encounter any massive bogholes on this track - however be aware - Wombat has pits that will swallow your car whole. Be very careful taking shortcuts Always test with a stick - if the stick sinks, it's deep mud. don't go by the water along.
This cache can be walked. From the north expect a very long walk in and out with some muddy tracks, or from Chettle Road, expect to climb a monster hill or two before you reach the cache. Hence the terrain rating.
Photo's aren't essential however would be nice.