>>53341854After beating the game fully and unlocking 5-star raids, you have to do the gym leader rematches and the Academy Ace tournament to get a call from Jacq, then do several 5-star raids (by yourself or hosting them, not joining other's) to get another call from Jacq in which he describes dangerous dens, which contain 6-star raids. Once you've unlocked 6-star raids, you can get the dens for the 7-star event raids too.
I believe there is a low chance of Herba Mystica in 5-star raids, with a slightly higher chance in 6-star raids.
