in the solar cave
waterfall pond 10F
You can retrieve HM Waterfall in Red Rescue Team by going to Solar Cave. There, you'll find assorted keys all over the dungeon floors. on levels 10F, 15F, and 20F, there is a locked treasure box with an HM in it. on 15F, Waterfall is in the box.
It is exclusive to Red Rescue Team, but if you get a mission that has Febass as the clieant he will apear in Waterfall Pond.
Waterfall Lake
In stormy sea (Dive is needed) , Waterfall pond (waterfall is needed), and other area's with water.
key door 15F solar cave
floor number 5
In Western Cave (You Can Also Find Mewtwo On The Final Floor)Although It Is Easier To Get Him In Waterfall Pond
waterfall cave floors 8-12 or a starter pokemon
You can get one at Mt.Freeze. Hope this helped ;)
Waterfall pond on floors 8 thru 12
Waterfall pond on floors 6 thru 12 the hm Waterfall is needed to enter the dungeon