There are roughly 300 possibilities for secondary monsters, but since each one of those can potentially blend with each other, the number of possible tertiaries rises exponentially in the tens of thousands!
They're much more complicated than secondaries, usually requiring two attributes from each ingredient or one more specific themed element that does not occur in a primary monster.
I generally try to stick to these rules. to keep things interesting, but inspiration can strike from anywhere! CURRENT COUNT: 154