Izuku's quirk is Summon. It is an emitter/warp type that allows him to "summon" anyone he thinks of to himself. It is a sentient quirk as well, giving a debrief on why the person was summoned while they're being summoned. It transcends time, so should Izuku think of someone who was dead or lost their powers, he can summon them at any point in the summoned person's personal time-line. The only catch is that Izuku must know vaguely what they look like.
Being summoned is a surreal experience. You go about your day when you close your eyes to blink and when you open them, you discover yourself to be in a tube of multicolored light that looks as if it is going at hyper speed. Then, you hear a voice that sounds as if it came from a goddess telling you why you're being summoned. Ex: "Do not be alarmed All Might, you have been summoned by Izuku Midoryia's newly awakened quirk Summon as you were the last person Izuku thought of before activation. When you next close your eyes, you will be met with a bullying situation. Deal with it as you see fit." To the outside world, you were covered in a rainbow of light before disappearing.
One downside of this is that it is a one-way trip. The summoned person has to find their way back. The only exception is if they are from the past, as which when the situation is solved the quirk will close the time warp and they will be transported back in time.
Combining with One for All allows Izuku summon himself to whoever he imagines, however they must be alive. He can't go back in time either. Same rules apply other than the one way trip.
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MHA Story And Quirk Ideas
FantasiStory/Plot and Quirk Ideas I have no motivation to make, but think sound really cool! The entries with Quirk : [Name Here] means this entry is about a quirk idea! The entries with Story: [Name Here] means it's a story idea! If they're combined, it m...