(SOLVED) Resource types and possible system for forgotten underground?

[FeelMyRash]

Hello.

I've been working on a map for a very long time, now. The basic premise is a magical stone summons all the armies of Azeroth (and beyond) to defend it from an onslaught of Faceless.

The map takes place in the underground lairs of the Faceless, far below the world in forgotten tunnels where no plant good enough for building grows (no lumber) and where metals are a rarity (no gold mines).

I've been trying to think of either new types of resources, or a way to gather the above mentioned ones without mines or trees (I'd prefer new resources though - ones that could work for every or most of the armies, so something that both Lordaeron and the Burning Legion could use).

I'll provide more information if needed.

Edit: I'm starting to think of something related to Crystals that could work...

 

[cleavinghammer]

Crystal deposits could stand in for gold, you could also do things like have NH crystal golems that turn into smaller crystal deposits after death.

Other possible mechanics (shamelessly ripped off from C&C); Neutral structures that switch to the last player that claimed them and periodically give resources, a new building for each faction that periodically gives a small amount of resources, respawning creeps that drop both resource types.

 

[FeelMyRash]

I ultimately went for having Power (produced by Crystals) replace Lumber and Energy (produced by Fountains) stand in for Gold.