Can you buy heroes in AFK arena?

I'm curious, can you actually purchase heroes in the game AFK Arena? I've been playing for a while and I've noticed there are various ways to acquire characters, but I'm not entirely sure if buying them outright is an option. If so, how does the process work? Are there any benefits or drawbacks to purchasing heroes compared to other methods of acquisition? It would be great to have a clearer understanding of the options available to players in this regard.