This activation key unlocks 20 Shell Recharge for Gemstone TD inside Dota 2. Shells are an in-game currency used to purchase additional Couriers, cosmetic content, and other special features available within Gemstone TD. Only works for the Gemstone TD custom game mode!

Launch Dota 2 and enter the game lobby. Open the ARCADE section from the main menu. Search for and select Gemstone TD / Gem TD. Join or create a game room and start the game. After entering the match, open the Courier Warehouse in the upper-left corner. Click the Redeem Code option in the upper-right corner of the window. Enter the activation code you purchased and confirm to receive your rewards.