Hi there! Now, I know everything is there on wiki, but I just wanted to make a guide to explain things (ie: how to get the factors, how much the combos cost, etc.)

"Breeding Factor A x Factor B, Combo x Factor A/B, and Combo x Combo all have the same chances to produce a combo-based cub. You do not receive a combo base buff for breeding Combo x Combo; along the same lines, you do not have less of a chance to produce a combo when breeding Factor A x Factor B."

This section of text taken from wiki means that everything is equal when breeding a combo base.
For example, let's use the combo base Arabica.
Arabica's factors are buttercream or buttermilk x black. This means that if you breed buttermilk/buttercream to black, you have a chance of getting Arabica. This also works for Arabica x black/buttermilk/buttercream. Arabica x Arabica would work too. Like it says, you don't have a higher chance to breed a combo base if you breed combo x combo, and you don't have a smaller chance if you breed factor x factor.
I made a suggestion about this! Clicky!

Let's start with the bases now.