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Along with the new expansion to be released in September, the design team is working on some fundamental changes in the combat/non-combat states, which may or may not be pushed live when the expansion is. The basic idea is to reduce the amount of downtime in EQ. Read below for all the details, but here is the executive summary courtest of Rashere as posted on EQPlayers:
"Once you have been out-of-combat for a sufficient amount of time, you can sit down (or be on a non-moving horse) and begin to rest. While resting, you enter an accelerated regeneration state that will quickly recover your mana, health, and endurance. For most single group content, once you are out of combat for 30 seconds you can rest. While dealing with multi-group content, that time is 5 minutes.