Strategy Event, Suggestions and Tips
Server: S15
Crowd controlling or AoE damage characters like Abraham and Kate will help you clear this without much issue. You can arrange your team centered on those characters in a variety of ways. For example, Magna for first turn pull and kill. Slower but safer Andrea, Shane, and Glenn combo for damage and sustain.
Choose strategies that work with the attack pattern you chose previously. Slower, sustain would benefit from things like new bloods, hp restoration, life steal, etc. Fast and pure damage would benefit from splash damage, extra damage from crowd controlling effects, or full preparation (20% atk if your hp more than 95%), etc.