Enriched Spell & Trap Zones

[Xytherior]

This is a concept that I've had floating around for a while- Spell & Trap Zones that have a special Spell/Trap Card activated within them to change their purpose temporarily. For example..

[spoiler="Mecha Nap-of-the-Earth"][/spoiler]

While this Continuous Spell Card is active, the Spell & Trap Card Zone that it occupies becomes Enriched. Enriched Zones are capable of holding cards on top of themselves, as visible with "Mecha Nap-of-the-Earth". Held monsters are still treated as Monster Cards and are NOT Spell Cards or Trap Cards.

Other possible effects for other cards could be;

• Holding spent Xyz Materials, and when a certain amount has been accumulated an effect activates. (XYZ)
• Activating Spell Cards on this Zone builds Spell Counters/ draws cards (S)
• Monsters held in a zone gain 1 Level during each End Phase, can be slid out during either player's turn (M)
• Cards Set over this Zone cannot be destroyed by card effects (S/T)
• While [card] is in this zone, it's name is treated as [card] (i.e. Gravekeeper, Necrovalley) (M/S/T)

Let me know what you think!