Thanks for showing interest in Lecheek Nutritions products. Majority of our products are made for stacking.
You could actually change up to to Mass HGH for 1 month to see how you like. Chances are you will want to run more than 1 bottle consecutively as most logs and reviews on here will tell you the same. (add oxy black if you like)
I saw no mention of Hyper T2 to stack with Oxyblack or the use of testadrol X9 to stack with Mass hgh and or AD3.
If we could get a little more background about you Training,diet,etc. we might be able to give you a more detailed direction to take.