Its look also differs in each title, but you still need to land at least three of them on reels. There is a separate icon for the activation of this attribute, called the “bonus symbol”. They don’t need to be landed on a pay line, anywhere is fine. Just land at least three scatters anywhere on reels. How to Activate Bonus Rounds in Slot Machines?Įach online casino where you play free slot games with bonus rounds in no download mode has the possibility to activate it. Once full, the system will take you to the mini-game. This meter gets filled up each time you land a particular symbol. In some games, you trigger the extra round after filling up a meter. There are different variations of triggering the extra features round.