The City of Zombies

"Death Surge" was the life-saving skill Shaun had acquired.

Each King-level creature possessed similar skills, making them even more difficult to defeat.

The cost and cooldown time required to activate it ensured that Death Surge wouldn't become a combat skill.

The primary reason Shaun was able to overpower the Eagle King was another rare skill he obtained when he advanced to a King-level creature.

Upon becoming a King-level creature, he received the reward for a daily system mission, "Ability Replication."

"Ability Replication: Can replicate certain skills or innate abilities of a creature! The replicated skills will be cleared after twenty-four hours. Cooldown: twenty-four hours!"

According to the system's prompt, this was also a rare skill, and its strength was self-evident.

The reason Shaun could overpower the Eagle King was because of this skill.

He replicated the Mutant Orange Cat's Limit Break!