The subs increase your xp rates how often you can talk in global chat and how long you can afk train before timing out. You can purchase them with $ via website or from other players in game. If you are an Ironman you must buy the subs on another account then multi log and use the sub on the Ironman.

Regular xp rates are 8x for combat 2x for regular skills and 4x for prayer magic and ranged...

A gold or below sub will add plus 1 to all rates above and a gold plus a platinum will bring you to 11x combat 4x reg skills and 6x prayer magic and ranged.

I hope this answers your questions

Hi Austin93,

Ghasp's post is accurate. For more details visit:
How to use store, subscriptions (In-Depth Guide)
Server Skill Rates

We hope you enjoy your stay!
Mod Billy

Server skill rate post is not up to date to reflect current rates also noticed it was wrong on morscape.... this would be a good post for a mod to redo and sticky ; )