In Captain America: Civil War, Peter is given a brand-new Spider-suit personally designed by Tony Stark/Iron Man, and in Homecoming, both Peter and the audience get to know the suit and its features a little more. It’s revealed that the basic mode in which Peter’s been operating is called “the training wheels protocol,” but midway through the film, Ned hacks the suit and disables that, so Peter suddenly has access to all the features, including hundreds of different web combinations and an artificial intelligence he names “Karen.”
In many instances, this proves to be quite useful, as Karen can educate him about the suit and provide things like navigation during the Washington D.C.-based sequences. Then it gets a little darker when she asks Peter if he’d like to try “Enhanced Combat Mode.” When he says yes, she immediately switches the suit to “Instant Kill,” and while we don’t get to see what that mode does, we do know it turns the suit’s eyes a menacing red. Peter immediately turns the mode off, but Karen brings it up at least on other time during the film. Now, superheroism is dangerous business, and sometimes that means putting an enemy down, but why would Tony Stark give something called “instant kill” to a teenage boy he’s specifically trying to keep out of trouble? Sure, it’s behind a training wheels safeguard, but still. It was so easy to access.