Blade of Four Energies DC / Spell Attack

[Almacia]

Just a quick question here.

The Blade of Four Energies (in Secrets of Magic) doesn't have a listed DC for the spells it casts, nor an attack roll for the one that requires it. The greater version does have a DC (but still no spell attack, though I assume it is about +28). I can't find any errata about it.

Is there an accepted value for this item or do I have to figure it out myself?

[Kelseus]

If you go to the GMG Creating Items section, it lays out DC numbers for the items of a certain level.

The level 18 version has a DC 38. This is the default value for spell DCs for a level 18 item. Using the same table, DC for level 13 items is 30, so that should be the item DC for the level 13 item.

For the spell attack rolls is a bit trickier. I think just cutting off the +10 works for that, so the level 13 and level 18 versions should have a spell attack roll of +20 and +28, respectively.