To get recruitment chests, you need to complete missions in BBQ Bash and in Events.

There are 8 types of character recruitment chests:

• Normal Recruitment
                                                 
• Specialized Recruitment
                                                 
  
• Elite Recruitment
                                                     
  
• Royal Recruitment
                                                     
• Snowfield Recruitment
                                                     
• Abyss Recruitment
                                                   
• Chaos Recruitment
                                                     
• Binary Recruitment
                                                       

You can get random characters by opening these recruitment chests, with different drop rates.