It is very important to select your choice of steroids according to your goal. Every compound has certain characteristics that make it more suitable to a specific use. For example- Trenbolone is not very good at bulking; however its fat burning properties are outstanding. So that will make it a very attractive addition to a cutting or lean mass cycle. Side-effects of each steroid compound should always be taken into consideration whenever a stack is planned. Never combine compounds that exert similar side-effects. For example- Combining Dianabol and Anapolon can be very dangerous as both are very toxic to begin with and combining them will only worsen their toxicities and that can do serious and irreversible damage.