Elysium: when does one use it?

According to the new errata, a Methuselah not involved in the current combat can tap the Elysium to end combat. When can he do this? - since he is neither the acting nor blocking Methuselah.

[ quoted text not captured ] According to the old ruling (not errata), it cannot be used unless you control one of the combatants There is no errata, new or old. -- Elysium: Arboretum, The - Master: Unique Location * May not be used if you have no minions in the combat. -- L. Scott Johnson (vte...@wizards.com) Official VtES Net.Rep for Wizards of the Coast. (*) - Subject to review by Rules Team