Avalon is a free to play game and rates as one of the most developed MUD's on the internet with a large array of spheres in which to play from it's second to none player vs player combat system, fully developed trade and economic systems, quests, roleplay and a large warfare mechanism. You want to raise an army of the undead? Yup. You can do that.
The land operates around 4 major cities who persist in varying states of conflict and are fully player run and whose spheres extend outwards to cover the numerous villages and hamlets that comprise the world. Professions are varied with unique takes on many of the major archetypes from Necromantic and Demon Summoning sorcerers who can transform into Vampires and various other forms and who can command black spirits and vile demons to Bards who can hypnotise with Dramatics and Song and attack enemies over whole spheres. Stealthy Nightblades whose rope trickery and covert knives lay waste and great mages who surround themselves in fiery rituals and call on Dragons as companions , the list goes on.
I started playing in the mid 90's and every time I've come back there has been something new to engage with from skills, improved systems, hidden specialisations and skills and as of this review I'm seeing almost daily updates and skill fixes and what looks like lots of new areas to be implemented in the near future. I don't have a great deal of criticism to level at Avalon as I've enjoyed all of my incarnations and play sessions on it.
Look me up, I play as Fu Leng, The Ghost Wind.