In powdered supplement form, creatine monohydrate is what you want. Creatine monohydrate supplementation increases phosphocreatine (or creatine phosphate) levels in the body. Look for creatine monohydrate on the ingredients list, not the label.
I am always concerned about running creatine with OX due to the extra burden it puts on the kindneys. A % of OX is eliminated via the kidneys - hence my concern. Also I want to keep the gains on OX, not just bulk up with water-weight.
For these 2 reasons i don't recommend Creatine of any kind while running OX...just good quality protein and glutamine...of course this is just my opinion though.
IMO from the research I have seen, assuming adequate hydration and creatine supplementation at the non-stupid dosing level, their is very little, if any, extra burden on the kidneys.