Mob Strength is a mechanic introduced in beta. It replaces mob level, since player level was replaced with gear rarity and artifacts in the Beta.
List of Enemy Strengths[ | ]
White: Very weak. Mostly reserved for farm animals, as they are the weakest mobs.
Green: Somewhat weak. Weaker enemies like brown Alpacas and Plain Runners have this strength, but they are not reccommended to be fought unless you have at least 1-star gear.
Blue: Somewhat strong enemies. Stronger enemies like Rocklings and Insect Guards have this strength.
Purple: Powerful enemies. Mostly found in dungeons, but certain enemies (like Lions or Chilings) spawn with a base strength of purple.
Yellow: The strongest enemies. Only the most powerful enemies have this strength, even in dungeons, and only a few have this as their base strength (such as a Collie). These enemies can pose a challenge to even players with legendary gear.