Hi Iceman, breeding pacmans will be a challenge! To create a rain chamber you can get an extra water tight tank and attach a pump with tubing leading to the top and then punching holes to create artificial rain. the water should be only one inch because pacmans drown very easily and should have access to haul out areas and plants for the female to lay eggs on. brumation periods will be required before attempting to breed pacmans. To read more there's a section on breeding pacmans in this care article Frog Forum - Pacman and Horned Frogs - Ceratophrys - Care and Breeding