Arcstone is a Legendary ring in Diablo III, added in patch 2.2.0. It requires character level 31 to drop. The unique affix works similarly to Fire Chains, pulsing every 1-3 seconds (depends on attack speed), both among followers and players. Each pair of wearers pulses twice independently, once for each wearer — with different damage (example: two rings with 1150% and 1450% damage will pulse once for 1150% damage and once for 1450% damage every period). The maximum radius is approximately 50 yards, and it can pulse even through obstacles (but not through solid walls). The lightning pulse is affected by all forms of increasing the lightning damage done.