Honkai: Star Rail has some systems that would be familiar to Genshin Impact players, like how their Eidolon mechanic is similar to Constellation. By obtaining copies of a character, people can activate the said unit's Eidolon Resonance, which will enhance their strength and provide new effects to make them more valuable in battle. However, similar to the Traveler in Genshin Impact, players can't get another Main Character, so Trailblazer's Eidolon can be obtained through other means.