In this video https://www.youtube.com/watch?v=JALiA9y-L90&feature=youtu.be&t=585, it seems that he said "nice thanks chat". In this context, the word "chat" means "audience"? Did he thanked for the audience? Maybe I heared wrong. I found some examples of "thanks for the chat"(https://ludwig.guru/s/thanks+for+the+chat), but I want to clarify it.
If you move the timestamp back a couple seconds, the player reads a suggestion from his chat room out loud out:
"You can always Innervate."
I'll avoid going into the details of Hearthstone, but he found it to be a funny suggestion. In response he says, sarcastically,
"Nice. Thanks, chat."
In this situation, "chat" refers to the audience communicating with each other and the streamer in the chat room that often goes along with livestreams on sites like Twitch or Youtube. He is sarcastically thanking those in his chat room who suggested he use Innervate.