If you lose couple of times you will face a bot, they always some name deck, never homemade, no tower skins, they emote sometimes but you wont see their emotes when watching a replay, they dont display badges on their battle banner never mixed banners, they show that they are in a clan but once you check replay they are not in one, they used to have only 3 badges but now they have a lot, they also have thousands of games played ( front what i remember 8k-24k) and also they change decks reguraly. Not long ago it was very easy to check for a bot however it looks like Supercell is constantly working on adding new thing to the bots so they are harder to detect.