DCs on dragon marks?

[imblo99]

For offensive ability dragon marks with DCs (storm comes to mind), are the DCs affected by:
Spell focus feats and items?
Heighten feat?

[andbr22]

normal -> Spell level + Cha Mod.

For storm is lv 3 (call lighting) or lv 5 (call lighting storm) of spell.
Metamagic should work, but highten highten level of spell, but you don't "own higher spell slots" so i would say it is ineffective.

shool (I am not sure) - evocation or conjuration i would say

[Hihiirokane]

Worth testing with a +1 DC item equipped, should show in the tooltip if it works.

[imblo99]

Worth testing with a +1 DC item equipped, should show in the tooltip if it works.

DC does not appear to be listed on the tool tip