Okay, so you are talking about servitors, not tulpas. As I explained, tulpas are not the same thing. People just misuse the term.
An true trulpa can be dangerous because it is an actual living being, as I said. It has its own mind, and feelings, and “soul” for want of a better word, and will do anything to maintain its existence. If you read the book I mentioned above, Magic and Mystery in Tibet, the author talks about how her tulpa went rogue and how she had to put down it down lest it destroy the local village (it had set fire to a building). It wasn’t easy to accomplish though.
Frankly, neither can I. However, there are many esoteric techniques that we in the West know nothing about due to knowledge being hoarded, or destroyed, by the Church during what’s popularly known as the Dark Ages, and by the fact that they are very closely guarded secrets in the Temples and monasteries where they are practiced.
Alexandra David-Neel, for example, does not provide the mandala she used in the creation process of her tulpa, and, from what I understand, had taken binding oaths not to reveal all she knew as a requisite for learning what she did.
A servitor can be dangerous as well, though not in the same way as a true tulpa. It can begin to subtly manipulate its creator to feed off their energy in order to maintain its own existence, if proper maintenance is not followed. It can harass and even try to scare those sensitive enough in order continue living. That’s why most authors recommend installing a kill switch into them during the creation process. However, it is actually a rarity for such a thing to happen with a servitor. In his book on the subject, Damon Brand states that in all his practice, he has only ever had one servitor go rogue and become a minor annoyance.
All I can recommend is that you read the two books I mentioned to get a sense of the difference between a true tulpa, and the Western idea of a servitor.