This build gets even more destructive while making use of Cedo, for extra status procs with the alternate fire before using Catalyze.

My Cedo build: https://overframe.gg/build/118454/

Lavos' 4th ability has built-in [Condition Overload], meaning that the more status procs you get on your targets before using it, the more damage you'll be dealing when Catalyze hits them.
So your general play with this build should be: Combine elements (by holding your ability buttons) depending on which faction you're facing to make sure your abilities hit the hardest they can. Your 2nd will be your most used ability as it has the lowest cooldown and it is capable of hitting status procs at a pretty decent range.
Your 1st is there to heal you incase you need and your 3rd should be used after your 4th to decrease it's cooldown.