Adrenaline: this principle makes it possible to spend Tokens equal to your current level of Fear. This is a mechanic to represent the power lent by desperation.
Tokens represent, in part, how interesting your character is. It is a common horror trope for characters to survive not because they are particularly intelligent or capable, but because they are interesting.
It is possible for player-characters to mutually talk each other down. They roleplay this interaction, and the GM determines when they can each spend a Token to reduce their fear.
Penalties from Fear and Pain are reduced to -1, -1, -2, -3, -4. In both cases, tests using Might and Might-related Traits have no penalty for the first level.
Single Traits can be taken more than once, but no more than 2 Traits can apply in any given situation. To help GMs manage this, when each character attempts something, the player should probably announce two Traits that they think applies so the GM has a chance to say “no, not this time”, etc. The GM may or may not announce Situational modifiers in return so the player knows what they are dealing with. For example:
Player: “Ok, I’m going to try to shoot the Zombie in the head to drop it. Sharpshooter 2, Clear-headed.” This means that the PC has a +3 to her Precision for this test.
GM: “Gotcha. But the zombie is surrounded by others, so its got Cover, and you’re Calling a Shot.” So this would be -2 to the PC’s Precision test, for a total of +1. Shooting a zombie is pretty easy most of the time – they tend to have a low Precision score.
In response, the PC can wait or move so the zombie is out in the open, shoot at another zombie not surrounded by others, or get closer to negate the problem of Calling a Shot (which is only really a problem when you’re some distance away.)
The goal here is for the rules to be fast, loose, interpretive and narrative. For groups that want more complexity in the rules for tests, they are free to have as many Traits apply as they wish, as well as any other modifiers, but bear in mind that this can really slow down the game.