Okay, so what if Warren had the same powers as Max?
Warren befriends Max pretty much immediately when she arrives at Blackwell Academy as if making it sure from the start that nothing happens to her. Also, Dana and Brooke point out that he follows her around and he always seems to know where Max is and bumbs into her all the time. For example in ep. 2 Warren can be seen from Max’s window halfway behind a building’s corner waiting for Max since they meet on the exact spot when Max walks out of the dorm building.
In episode 1 on the parking lot Warren tells Max about his car being made in 1978 and Max says that he’s ‘in the wrong time’ to which he replies that so is she.
In the end of the episode Max gets a message from Warren with him referring himself as Max’s ‘white night’ with a pic of his black eye. Max answers that she’owes him one’ and Warren mentions about Max’s ‘big secret’ which she hasn’t told him yet.
In episode 2 while Max and Chloe are in the junkyard Warren texts Max that she can ‘hit him up anytime’ if she has more questions about time travel as if hinting her to tell him about the powers. Warren also refers himself as her ‘personal superhero’ and mention Chloe saving Max’s ass in ep. 1 seemed to make Max glad to see her appearing out of nowhere ‘like a rockstar’ - which he does himself in ep. 4 in the boy’s dorm’s.
In episode 3 Warren helps Max to built a bomb and later on asks if she blew up with it, but doesn’t really give any hints of the powers.
In episode 4 in the boy’s dorm scene he acts so differently, as if he knew what happens and has seen the result of Nathan’s actions - aka him shooting Max and Chloe. Before he rewinded to save them he heard gunshots outside his dorm room and then rushes there just to see Nathan with a gun and Max and Chloe laying on the ground, both dead. After he rewinds he even says ‘Max, I got this’ confident about what’s going to happen. He’s pissed off and doesn’t react on Nathan having a gun - like he knew all along that Nathan was carrying it plus he isn’t scared of it. Also he can predict Nathans movements and react to them instantly, kicking the gun off his hand without hesitation or surprise on his face and then beating him up furiously. So he might have rewinded again - and again, who knows. His shirt also changes during the scene along with Nathans face from blood stained to not blood stained - he rewinded and changed his possibly bloody shirt to another very similiar one to fool the others.
Before Max and Chloe enter the Vortex club party Warren appears and insist on taking a photo with Max - maybe to get back on that moment through the photo like Max did with Chloe’s dad’s photo. In that way he could save Max later on after he finds out who is behind all of it. He also says that it just might be the ‘end of the world’ and ‘One picture with you, that’s all I need’.