Also now that I think about it...many vets here says gh, test, and slin is all you need.
This is all common sense. Plus everyone has a different opinion and response so again use common sense. Some hate nandrolone whilst others love it. I personally think it's probably a better muscle builder than test. However, no one really wants to be on 2 grams of deca whereas many love that amount of test. I know many who say the higher dose of test you go the better whereas others can't go above 500mg without feeling like complete crap.
The reason many vets say those 3 is because they are all produced naturally. Many also believe it's healthier to use that combo instead of adding in exotic compounds such as tren and mast etc. I also agree in combination you are not going to get a better muscle building stack than those core 3. Does that mean deca or any other aas are not worth using... hell no.
Plus all you need and what works optimally are 2 different things. Granted when bulking you don't really need more than those 3 and combined with a great diet/training they should produce insane amounts of muscle mass over a long period.
Again just use common sense. If you have used them before you must know how you respond to each. If not then experiment more or just stick to what you know. Me personally when bulking adding in a little deca only adds to things as my joints feel better and I get stronger. Many love tren when bulking due to the strength and body composition changes. There is no set way. One of the freakiest guys I have seen would bulk on about 3 grams of test and 2 grams of tren and would swop out the tren for 2 grams of deca at times too. Every aas can bring different positives so just find out which ones give you the most positives and the least negatives.