AWS WAF, AWS Firewall Manager, and AWS Shield Advanced
Developer Guide (API Version 2015-08-24)

AWS Shield Advanced Limits

AWS Shield Advanced offers advanced monitoring and protection for Elastic IP addresses, CloudFront distributions, Route 53 hosted zones, or Elastic Load Balancing load balancers. You can monitor and protect up to 100 of each of these resource types per account. If you want to increase these limits, contact the AWS Support Center.