wpDiscuz Advanced Likers add-on is the light user reputation system allows to display different rating titles and badges based on amount of received likes. The rating titles and badges come from wpDiscuz.

More info here: https://gvectors.com/product/wpdiscuz-advanced-likers/

If you use the wpDiscuz – myCRED Integration add-on the comment authors get points if their comments have been liked/voted up, and they’ll lose points in cases dislikes/down votes. This «Like to Point» feature also works for voters, they can get a certain amount of points for comment voting. wpDiscuz – myCRED Integration addon also displays member badges and ranks under comment author avatar and label. And the badges and ranks come from the myCred plugin. 

More info here: https://gvectors.com/product/wpdiscuz-mycred/

Can they be used together, or should only one be used at a time?

Sure, you can use those two add-ons together.

I've purchased the wpDiscuz Addons bundle and I'd like some clarification on reputation/badges. Advanced Likers has a user reputation system, but there's also a myCred integration extension. Can they be used together, or should only one be used at a time?

Kind regards.