Celebration Lamps is a Treasure Hunter promotion originally released in December 2016. During the promotion, all the lamps and stars are replaced with celebration lamps which provide experience in a chose skill equal to that provided by the respective prismatic lamp, while additionally providing 5% of the experience gained in the chosen skill to all other skills. Experience provided in elite skills is scaled accordingly. Every 10 lamps celebrated boost the experience gained by 2% more, up to a maximum of 10% extra experience.
During the original and the December 2017 promotion, A global 10% experience boost was activated for all non-ironman accounts to celebrate the new year. Players received the following message upon logging in:
Bonus XP is now active! Earn 10% more experience to celebrate the New Year!