Hotels with Waterslides in Saas

"Whatever you remember about youth hostels, this ain't it. Modern, clean, not cheap (it's Switzerland), and it has a very nice wellness spa for a rather reasonable additional charge. Food is good but not fancy, and staff were extremely helpful. The only glitch was that I booked this stay with OneKeyCash, and hotels.com (i.e., expedia) took my money and gave me a receipt showing no balance due, but then didn't actually pay the hostel! That led to lots of extra work for the hostel staff to straighten things out. I would rate the hostel itself at 10/10, but hotels.com/expedia at 0/10. "