Is there even a way to combine monsters in MR3? I cant seem to find it...All the other games had it and I loved it...but not this one...

Unfortunaley you cannot the only thing you can do is raise them in an area till they change.

Wait, they change in MR3? I sort of missed out on this one and skipped ahead to four, I had no idea that they had done away with combining monsters in this incarnation. =/ How does this new changing system work, do they just alter in accordance to the environment or to other monsters?

They just more or less change how they look for example a suezoe raised in the goat ocean region may turn into Fuzako which in other games is a suezoe lesione and looks aquatic if you want a better chance of them changing feeed them that food for that region like Jungle and mango.