1. Non-gift magic (The Mythos) and supernatural inhuman (alien) technology is powerful, yet dangerous. Black tech and the Mythos can always botch.
These effects and abilities tend to be much more powerful than single gifts, or unique in effect.
2. If a PC enters a game plotting to kill another PC, they must roleplay and give their potential target a chance to notice something to arouse suspicion and paranoia: at the very least, sideways glances, sneers of disgust when they arent looking, etc. You can pm the GM your intentions and let them handle the rolls if you would like to do so without giving meta knowledge.
Non-world artifacts and conditions must be cleared with the world leader before play, otherwise their effects can vary wildly, entirely up to GM discretion.
9 gift characters must pass a 'Seasoned Test' in order to achieve their 10th win- this need not be solo, but will be especially difficult and often highlander.
Characters with 4+ gifts must have something that puts them into conflict with other PCs, NPCs, or a goal in conflict with the world's status quo.
Driving goals must be nailed down by the 4th win. Characters are expected to keep their driving goal in mind- it is what pushes them to endanger their lives repeatedly for vague promises of power after all.
Organizations play a large role in this world, with remarkable rewards and bonuses available to those with initiative. Supernaturals going public as a rogue tend to disappear and fond employment, tight lipped about their decision. The most effective way to maintain relative autonomy, is to preemptively choose and ally yourself with powerful allies. The military and governments, large and small are constantly on the lookout for new talent, but they are by no means the only opportunity- Successful businesses have their own assets, and corporate espionage is a constant threat.
The 'Mythos' of HP Lovecraft and other related authors are part of this world-
Revelations that conflict with your understanding of the world, and things that Should Not Be will trigger trauma rolls at difficulty 7, as per a trauma roll. A failure causes 1 mental damage and a short lived negative reaction. A botch or -2 or less also adds a trauma.