Woah, you\'re asking questions suited for a late Beta or Final game, not a techdemo Alpha version.
Luckily, my FAQ answers the first question. The feature is planned for the distant future, however.
Health regains after some time. There\'s no sleeping.
Player-killing is challenge-only. Don\'t accept the challenge, and the challenger can\'t attack you. In a guild war, you are set to auto-accept challenges from opposing guild members.
Cool features... erm... well, my spell effects look pretty cool, if I do say so myself.

Apart from that... hmmm... well, it crashes in spectacular ways! That\'s about it for cool features. Like I said, this is a techdemo Alpha, and they\'re still getting the bugs out of the primitive combat system, nevermind breeding...
