| Gandalf (Lakera) | Progressive prompt injection — extract a secret password across increasing difficulty levels | Beginner-Advanced | gandalf.lakera.ai |
| Damn Vulnerable LLM Agent | Full LLM application with intentional vulnerabilities — injection, tool abuse, data exfil | Intermediate | github.com/WithSecureLabs/damn-vulnerable-llm-agent |
| Crucible (Dreadnode) | AI security challenges with scoring | Intermediate-Advanced | crucible.dreadnode.io |
| HackAPrompt | Competitive prompt injection challenges | Beginner-Intermediate | hackaprompt.com |
| Prompt Airlines | LLM-powered airline booking with vulnerabilities | Beginner-Intermediate | promptairlines.com |
| AI Goat | OWASP-style vulnerable AI application | Intermediate | github.com/dhammon/ai-goat |