Since most of casinos in this forum have mandatory KYC rules, there's only few casinos that free KYC e.g. Freebitco.in, Anonibet and BCH.games. Freebitco.in have a good reputation in this forum and the representative are very active, I recommend this casino. While Anonibet and BCH.games seems there's no activity anymore, so if you have faced a problem, you will be hard to contact them and their reputation isn't really that good.
Along with those ones, Nitrobetting is known to not ask KYC, same for Bitvest and its brother 777coin already mentioned by buwaytress above. Yobit also provides few games and never requires any KYC. Peeps Place also quoted Betcoin and Playbetr on another thread but I'm not sure they don't require KYC for high rollers.
Only fully decentralized casinos would be totally safe, but we are still waiting for their release.
Nitrobetting, Betcoin, Playbetr, Freebitcoin are sites that never ask for KYC unless you use a VPN.