Launch bolt is not in the SRD so it needs special permission from QM
@DragonParadox will you allow it?
Also, IIRC it is a fairly useless spell since all it does is shoot a bolt we already carry as if from a light crossbow, we might as well carry a crossbow.
As for arcane mark being useless, not so.
1. It really helps with scrying. - actually that seems to have been a houserule, I can't find a source for it.
2. It lets us summon the object marked into our hand later on.
We could put it on the crown, that way if we ever lose it we can summon it to us. we can put it any item of high value we have. We could put it on a weapon
And we could put it on our sister and familiar to make scrying for them easier if we ever get separated.
mostly i am taking it for the crown though
... why not use acid splash instead of launch bolt?