Supercell is finally giving Builder Base some love. The Builder Base Hammer Jam event runs from May 17 to May 31, 2026, and it’s a full two weeks of 50% off upgrade costs and times — including the Star Laboratory. You also get a 4x star bonus, extra event tasks, and free Clock Tower Potions and Star Jars. If you’ve been ignoring your Builder Base, now’s the time to jump...