mdma is pretty safe by itself, most common problem leading to health issue is water intoxication/ hyponatremia. I've read in Illegal Drugs a complete guide to their history chemistry use and abuse , that it would take est. 12-14 average MDMA caps to cause fatal tox. however all people are different and react differently to drugs so its always wise to satr with a low dose and see how you react.
also another good site for info on common party drugs, check out tripproject.ca
as legal xtc, there are several blends /chems being labelled as such. Benzylpiperazine (BZP) as referred to above, is one of the more common untill health officals started shutting it down. It on its own is equiv to dextrophetamine, about 10 % the potency of meth. When mixees with other pipes, mainly tfmpp, it mimics mdma. other pipes include mcpp, pfpp, meopp. Most people dont like these as they tend to cause horrid hang overs head aches, stomach upset, insomnia, to name a few. Claims of it being herbal has been debunked , they said it was a natural pepper extract, but later proved to be purly synthic
BK-MDMA is also one of the more popular herbal e's out there. effects are said to be just like m but without the empathy. Will let you know next week lol. As a party pill supplier in canada recently stock EASE and I have order some.
Also theres NRG-1 (Naphyrone) which are in some herbal e, aswell as dmaa( Methylhexanamine ( Geranamine), and lsa.
Thats just a couple of the herbal e's in the scene right now. For more information search party pills