The following contains spoilers for Episode 10 of Chainsaw Man,"BRUISED & BATTERED", now streaming on Crunchyroll.
While the humans and hybrids in Chainsaw Man make pacts with devils, giving them demonic power beyond mortal comprehension, there are some twists to those deals. Firstly, the contracts usually shorten lifespans, as seen with Hayakawa's Curse Devil giving him two years to live, and Himeno, whose pact with the Ghost Devil ended her life in the bloody battle against the Samurai Sword.
Even Denji has a massive restraint in that his body becomes depleted once he loses blood; without this fuel, he's far more vulnerable. It could lead to his death, which is why he has to consume more of his enemy's blood in the field. Coincidentally, the chaotic Power also has a major issue that could handicap her in the line of duty, making things tough for Makima's crew moving forward.
Chainsaw Man's Power Becomes Anemic
Following the attack on the Public Safety Unit, Makima wants to recalibrate; she survived an assault so is now making a new division, which leads to Kishibe teaching Denji and Power. However, the sessions result in him killing them, feeding them blood and the teens resurrecting, all due to their abilities.
They try to ambush Kishibe later on at his home, with Power using her blood to create spears and such, trying to impale the teacher. It's all part of his sadistic game, but after they fail and he beats them down, he admits Power has a huge problem. She becomes anemic by using her blood to make these weapons, which leaves her very tired and open to attack. In fact, it could result in a skilled enemy killing the de-energized Power, especially because they wouldn't revive her the way Kishibe does.
Chainsaw Man's Power Needs New Solutions
Now, this could lead to Power adapting for the future. She can try to use her enemies' blood to make her hammers, spears and rain of knives, saving her own blood. Or she could roll with blood packs, which Kishibe uses to resurrect the trainees. Power may also need to hunt stronger devils, mix their blood with hers or keep them in blood packs too, as imbibing this elevated blood makes her more powerful.
Assimilating blood like this and becoming a parasite of sorts is something Makima's science team can easily look into. They need their soldiers as strong as possible, after all, especially because they still need to hunt the Gun Devil after taking out the Samurai Sword.
Ultimately, Power is just as big a weapon of mass destruction as Denji, so Makima has to get her up to par ASAP. Power can easily turn the tide but if this drama isn't fixed, the teen won't be as big an asset. This is a dilemma that Makima can't afford right now, with mysterious assailants targeting them from all corners as Chainsaw Man continues.