The Holodrome Iron Mountain Playset prototype is shown below. The original figure cardbacks had a picture of this on the rear of the card but alas! It was never made for sale. The text on the image below reads:

Enter the Holdrome if you dare! Steeped in the legends of olde, it’s the magical mountain where Merklyn and the Mages of the Mist reside. Together, the Visionaries valiantly struggle to reach the top of Iron Mountain and witness Merklyn’s ghostly apparition.

• Holographic dome built into the mountain top, reveals the moving, three dimensional, ghostly image of Merklyn. Kids can actually put their hands through the image!
• Built-in, synthesized microphone lets kids be the voice of Merklyn, the Holodrome wizard.
• The path to the top of Iron Mountain is filled with treacherous pitfalls and obstacles- features 2 trap doors, hidden mountain caves, a falling rock bridge and swing away rock hazard.
• The Holodrome has detachable hover pods which the Visionaries use to fight their magical battles.
• The twin mountain towers have rotating gunner stations that can each hold one figure.