http://www.lasvegasadvisor.com/greatdeals-slotpromotions.cfm
Hard Rock - Sun & Mon: Mystery multiplier.
Maybe I'm wrong, but it looks like this mystery multiplier is only for Shopapalooza Gift Card Points, not regular points.
Per their website -
https://www.hardrockhotel.com/las-vegas-specials/hotel-deals/2x-gift-card-points/815