Why didn't Pro heroes help NightEye


First of all, i didn't read the manga, so if the answer to this is a spoiler,
please abstain or mark it as a spoiler so i can avoid it.

My question itself is a spoiler for those who didn't see Season 4 yet:

> As we have seen in season 4, NightEye was gravely injured, survived long
> enough to be put in a hospital, until he died. Why didn't pro heroes use Eri
> quirk to save him ? rewind can cure his injury. If you say "Eri was sick",
> why didn't they bring Neito Monoma, the kid with the Copy quirk ? he can
> copy Eri rewind and save NightEye, it's not like it's going to take a whole
> day.

**Edit** : Also Aizawa was present to cancel the quirk if it gets out of
control




**Neito Monoma couldn't use Eri's Quirk, because it is not compatible with his
own Quirk.**

Although Neito Monoma can indeed copy any Quirk, he only copies them in their
"base" state. We could say Neito Monoma obtains the Quirk as if he was a baby
and the Quirk manifested for the first time.

When Neito Monoma tried to copy Deku's Quirk, he found himself devoid of any
super-strength. As he explains himself in _Chapter 217_ , since Neito copies
Quirks in their base state, **any Quirk that needs to charge up or stock
something over time to function is useless to him.** He correctly guessed that
Deku's Quirk only stockpiled strength over time and didn't simply grant him
super-strength. Similarly, Neito Monoma cannot use Fat Gum's Quirk as it
relies on cultivated reserves of fat to function.

We have seen that Eri's Quirk,
[Rewind](https://bokunoheroacademia.fandom.com/wiki/Rewind), depends on the
length of her horn to function. As she uses her power, she depletes her
reserves and her horn gradually shrinks. This means she had to grow and
cultivate that horn to use her power ; in other words, Rewind needs to
stockpile _something_ to function.

Since Neito Monoma's copied Quirks can only for only 10 minutes at most, he
absolutely does not have the time to stockpile whatever Eri needs to activate
her Quirk.

