TRIFECTA
I signed up for a Spartan race last year and found the above code for 10% off the race. I've just signed up again for the next Sydney race and it is still working!
There are races all over Australia at all different distances with the next ones as follows:
http://spartanrace.com.au/event/sydney-anz-stadium-race-15-f…
http://spartanrace.com.au/event/melbourne-super-7th-march-20…
http://spartanrace.com.au/event/perth-sprint-18-april-2015
http://spartanrace.com.au/event/brisbane-beast-16-may-2015
Prices are cheaper the earlier that you register (start at $105 before discount) so get in early to save the most $$!
I have completed in heaps of different obstacle races / mud runs and the Spartan ones are the best imo! They are a good challenge for any fitness level!