People should know that false teachers will teach anything they believe, and not from the Bible. People also should look at the preachers their behaviour and see if they have the Holy Spirit in them, following, living according and teaching the words of the Holy Bible. Often their way of talking, using a language which is not according the way Jesus would talk shall dismantle them and should be a sign for you that they are not the right one to follow.
In the history of Christendom we see many churches which started of as so called cults or so called heretic movements, though many years later they sometimes outgrew their original group and/or became one of the many main churches. Therefore one should be very careful by damning a group or calling ti a cult or sect, when there is not really anything what qualifies it to become called a sect or cult.
There are people who want us to believe god had to purify Himself but that we ourself do not have to do any works any more or can do whatever we want because God brought salvation to us by His death, though God can not die. By such misleading teaching those 'preachers' are fooling not only themselves but are taking the opportunity away for others to find the Real God of gods and the entrance to the Kingdom of God.