Fine for Yukiko's speed. Though, she's clearly far faster than Misuzu as even her has great trouble keeping up with her.
I do remember however that she was blown to pieces during a fight on the track field and she recovered from it quickly. Maybe the pieces were big, but she was definitely in pieces.
For Phantasmagoria (PG)...
- When she cast her power on Ira, it created a beam that disintegrated his arm and Kukuri's chains. At first, it seemed that it was ability negation, but we later learn PG is an illusion-based power that is so strong it affects other aspects and can be categorized as other powers. Illusion Creation: [Ô£ô]. However, the fact that Ira's arm was gone clearly wasn't an illusion, same for Kukuri's chains, meaning her illusions have an impact and can affect and warp reality. Reality Warping: [Ô£ô]. Also, despite being illusion-based, the fact that she canceled Kukuri's chains remains. Power Nullification: [Ô£ô].
- Against Misao's time bomb on Invidia, Yuka's power that was casted on Invidia relayed back to Misao who unconsciously lost the willpower to maintain the spell active. Willpower Manipulation: [Ô£ô].
- When she used her power on Kakeru, it ended up affecting the entire city where Kakeru and the other Fragments had forgotten about each other and the Red Night. Memory Manipulation: [Ô£ô].
- The power used Kakeru's happiest memories and his subconscious desires to create an "illusion" based on them, which in turn affected his feelings, as he stated it was the happiest he had ever felt in his life. Empathic Manipulation: [Ô£ô].
- At base, illusions are tricks on the mind, but since Phantasmagoria is so strong, it directly affects the mind into believing what the caster wants the target to believe. Mind Manipulation: [Ô£ô].
However, I also realized something else. Yuka used PG on Kakeru while they were inside the Red Night, right? This "illusion" transported the entire city outside the Red Night in a normal day like nothing had happened. When Kakeru eventually realized it wasn't the real world and Yuka canceled her power, they were BACK in the Red Night but the time that passed was equal to 1 whole day, the same time that passed in the "illusion". We know that time flows very slowly in the Red Night: 6 months in RN = 64 years in real world. Yet, the 1 day passed in real-world time, despite the fact Yuka activated her power from inside Lieselotte's PG. And we KNOW the 1 day thing is correct because CrossVision shows it like that as well, but when they are back in RN, they are at the same location they were when Yuka used the power. The thing where time flows differently between RN and real-world sounds like 2 different dimensions to me.
And Yuka's power can't be an illusion in this case, since she activated it from within an already existing PG. There is no way Yuka would have fooled Lieselotte if it truly was just an illusion, especially since the reason Yuka can use the power to begin with is because she has a Void Fragment, aka a part of Lieselotte. And EVEN if she had fooled Lieselotte, the fact that the flow of time coursed normally in Yuka's PG proves that she created a different dimension.
If it really was just an illusion, just because Kakeru would have felt time flowed faster doesn't mean it actually did. 1 day normally = 0.56 seconds in RN. 1 day in RN = 4 months normally. It clearly isn't the first case, since CrossVision tells us that 1 day passed and CrossVision measures the flow of time in the natural course, not RN's course. And it's also not the second case, as the time Kakeru and Yuka passed together inside the "illusion" definitely isn't 4 months.
Which means Yuka created a pocket dimension inside a pocket dimension, which is why time passed with the normal flow and not the RN flow. Pocket Reality Manipulation through PG: [Ô£ô]