Ethereal, summons and weapons

[GrudgeBringer]

I understand that an ethereal being gets a 75% chance that an opponent may 'miss' when attacking unless it is a magical weapon.

I ran into something that makes me wonder if we need to expand the definition.

I have always assumed (yes, I know what that does)that unless a weapon is actually labeled magical it is deemed to be conventional. Soooooooo, if you have a summoned unit is its weapon considered magic even if it isn't noted? I mean it IS a magical being...

What has made me think of this is a battle I just had. I had about 30 mystics and all where buffed with Etherealness. A Tart jumped me and hit me with Rain of Stones and wiped out almost ALL of them.

I understand that Rain of stones IS a spell..and a spell I would guess is magic by definition. So I guess I am wondering if ANY and EVERY spell is considered magic in regard to units regardless of what the spell is.

Dumb question...maybe, but I honestly thought that a spell like Rain of stones would be more conventional than say..Pillar of Flame.