Mechanics in Fledgling are intended to be resolved as painlessly as possible. Due to this, all conflicts are treated uniformly: whether a Subterfuge check to pick a lock, or a Battle check to return fire at a guard. Given a challenge, the GM responsible will set a difficulty score to overcome it which the player must roll equal to or over to succeed. GMs are intended to set difficulty scores based on the act your character is attempting - while closing 40 yards to punch SCP-682 and taking cover and shooting at SCP-682 are both Battle checks, the 'take-cover-and-fire' check will almost certainly have a significantly different difficulty. Remember that cleverness in your approach to situations will benefit you. Success means that the challenge has been surpassed in whole or in part (for example, a rampaging SCP-682 will not be defeated by a single Battle check). Failure will inflict some sort of negative condition on the PC and potentially the PC's team, depending on the situation. Negative conditions are as follows - temporarily additional scores may be instituted for a run at the GM's discretion:
Injuries: This should be obvious. Combat wounds, sprained ankles, some kind of bizarre wasting disease, whatever.
Stress: Like injuries, but for when you see things Man Was Not Meant To See (tm), or you encounter a highly distressing situation.
Suspicion: Cheese it! They're on to us! Whatever you're doing is rousing the suspicion - and ire - of those around you.
If any of these get too high (3+), your character is removed from active play for the session. You may play out your removal, but you can no longer aid the mission in any way. Your character may hinder the mission at the GM's discretion.
After a session is completed, all negative conditions are reset to 0. Players are strongly encouraged to play out the results of their defeats - whether the enemy was able to gather information on you because Suspicion maxed out, or you're nursing a limp due to your Injuries, you should not come out unscathed.
Caveat: The Blood Runs Cold
In some situations, GMs may decide that a situation is of such gravity that it merits more grave penalties for failure. In this case, the GM will issue a warning in-character, narrating that the PC's blood runs cold. In this situation, raising a negative condition to 3 or above results in the removal of that character from play permanently - whether due to death, capture, or other grim end.