Those once a day gachas are giving tickets for RG stones after maintenance. I've been buying them this week to see what I get.

Rainbow Sublimation Stone × 1 25.00%
Rainbow sublimation stone × 2 40.00%
Rainbow sublimation stone × 4 15.30%
Rainbow sublimation stone × 6 8.00%
Rainbow sublimation stone × 8 6.00%
Rainbow sublimation stone × 10 5.00%
Rainbow sublimation stone × 50 0.50%
Rainbow sublimation stone × 100 0.10%
Included in the premium gacha
One of the 6 characters x 1 0.10%

Hope I get lucky!