What dose "lost" mean here?
Native speaker’s answer
Rebecca
"Lost creatures" in this case refers to the members of the Avengers, who were gathered together at the last minute to stop Loki. Loki calls them "lost" here to mean that they are helpless. So "lost" in this case has the meaning of being helpless, good-for-nothing, and worthless. Loki uses this word to insult them in hopes of making them less confident.