Character meet and greets

Hi everyone,

What tips can you all give me on the character meet and greets. We are taking our first to to epic next month and we are die hard Mario fans. My son is soooo excited to meet everyone from Mario. How do the character meet and greets work. What are the times? Is it all day or specific times? Are the waits typically long? He’s also a fan of toothless too so we would want to do that as well. And the meet and greets don’t accept express pass right?

I appreciate any tips!! We want to make the most of our time there because we are only coming for 3 days. Thank you so much!