Followers warning when casting summons
With magery the warning is before you cast the spell, with spells from other schools like Colossus, the warning comes only after you cast it and try to target an area to summon it. All of the summon spells should just work one way, probably like magery..where the followers check is done when you attempt to cast it. Although that blocks you from pre-casting.
A qua lemmúr wíste, an zen anku vol verde wís.