Is Sidus Heroes free to play?

I'm curious to know, is Sidus Heroes a game that's available for free to play, or does it require some form of payment or investment to access and enjoy? I'm interested in the game's monetization model and how it might impact the overall player experience. Can you provide some insight into whether or not Sidus Heroes is a free-to-play game, and if not, what kind of costs or investments are involved in participating in the game?