Sorcerer with Metamagic Master feat

[Dayton]

6-lvl Crossblooded Sorcerer(Orc and Draconic bloodlines) wants to cast Empowered Burning Arc.
He has the Metamagic Master feat so the Level Increase goes to +1 instead of +2.

6-lvl Crossblooded Sorcerer has 0 lvl-3 spells known, due to the Crossblooded penalty.

He argues that he can cast it because he still has lvl-3 spell uses, even though he has no spell known.

From one perspective this is correct. On the other hand, how can he sacrifice a lvl-3 spell use since he has no actual lvl-3 spell.

What do you think guys??

[Claxon]

You've (accidentally) posted what looks like a question about Pathfinder 1st Edition in the 2nd edition forum.

But to answer your question, a regular sorcerer would have three 3rd level spells per day and one 3rd level spell known.

A cross-blooded sorcerer knows 0 3rd level spells. But can use their 3rd level spell slots to cast other spells, including metamagic spells which have a final adjusted level of 3rd. They can also simply cast 2nd level spells out of 3rd level spell slots (if memory serves me) at no benefit though.

[Dayton]

Thanks, it makes sense.
Sorry for the "mispost".