Thermal Foundation adds blaze variants which are the blizz, the blitz and the basalz. I would like to have support for them please. They should at least be able to fly because I think that it's pretty easy for you to add. But they also have special abilities because just like the blaze they shoot projectiles.
The Blizz shoots projectiles that look like blizz powder and give slowness III to the target.

The Blitz shoots projectiles that give blindness III.

And the basalz shoots projectiles that give Weakness III.

Don't use infos you find on the wiki because they are outdated.
Here is the mod's source https://github.com/CoFH/ThermalFoundation

I don't support other mods (only fixing some bugs that can fix stuff with multiple mods), but can't you find those blazes in creative morph menu?

I can morph into them but I can't fly.

Yes, indeed, you need to configure them manually. Check out morph configuration. I guess fly ability and small_fireball action should do it (fireballs would be without debuffs tho).

Ok thank you I was not aware that I could configure this type of thing in your mod! ;)

It won't add those effects to the fireball, but at least it's something. I'll try in the future to make the configuration as flexible as possible.