Only if there's a chance of the usage being misleading. Otherwise the usages are supposed to co-exist.
Anyways, the scrolls they refer to are actual scroll objects. They aren't using it in the slightest bit creatively.
A trademark on a game called 'The Sword of the Kingslayer' might conflict with another game called 'Spell for the Kingslayer', as they both follow the pattern '_ of/for the kingslayer' and kingslayer is a relatively unique word. Sword and spell are not.
> if I created a new game called "Warcraft"
Did Mojang create a game called TES: Oblivion? No.
So the appropriate analogy would be you creating a game called 'War', a generic thing not invented by Blizzard and not in any way exclusively associated with their games.