The Sylvari are a bucnh of humanoid plant people who are grown from an ancient, sapient tree that gives them a linked inter-connectedness to said tree. They're not really born so much as all pop out of pods from this tree, where they all have a big ol' inter-connected dream world while they grow up, made up of the experiences of Sylvari who've grown up and left. Also has slightly resulted in a few seperatist groups, the Soundless who've cut themselves off from that inter-connectedness, and the Court of Nightmares who've gone to go for the darker side of the dream, not happy with how other Sylvari do things and with a general attempt to corrupt others to their way of life