You don't have to be interested in the subject. Nobody is interested in everything in a conversation. But if you back up a level and think about teaching your kids how to interact with people, that is something you probably can be interested in.
To this end, ask them questions about what they're telling you about. "Boards aren't immune to spiders? What do spider'sspiders do?"
What you're doing here is teaching them how to have a conversation, a back-and-forth with someone. They think they're talking about a game. They're actually learning the back-and-forth dance that is a conversation.
After some back-and-forth, you can end the conversation: "Thank you for telling me what you know about X! I like knowing more about you. I'd like to go back to doing Y now. Can I have a hug?"
It's also OK, when you genuinely can't talk right now, to tell them that. "Wow, that sounds really cool! I'd like to talk about that, but I can't talk right now. (Offer brief explanation if appropriate). Can we talk later?"
The goal is to teach by example how to converse, and how to advocate for one's own needs in a respectful manner.
