Hey there! I’m kinda new here and I know this is probably a silly question but if I want to get an S rank ark out of fusion do I need to put 2 S rank arks in? or could that potentially not even yield one? Thanks!
In order to get an S ranked ark from fusion, one of the arks needs to be an S rank. The other ark being fused must at least be an A ranked in order for the newly fused ark to be an S rank. For example, if I fused an S ranked Gremly with an A ranked Knighthawk, I will get an S ranked Gremknight. If more than 2 monsters are being fused, then you’ll need multiple S rank arks.
Two S ranks makes an S rank ark. I cannot remember if and A and S make for sure S rank.
Edit: darn milk beat me to it xD he pretty much got it though :3
Thanks that’s great news! 
A and S are 50/50 % chance of getting an S
Argh, this is the third time I’m answering the same question. But basically, you don’t need 2 of the same grade, just use 1 grade that you want and 1 grade that’s 1 lower than that, eg. S and A. It will work out to S grade 100%, if you want to know how it’s done then go to general discussion there’s a thread there where I posted the method to working it out.