Friend or Foe?

is the thirteenth episode of Kamen Rider 555. It is the fourth and concluding episode of the Kaixa Gear arc, culminating with the debut of Masato Kusaka, and his first transformation into Kamen Rider Kaixa.
==Synopsis==
Mari, Takumi, and Keitaro begin looking for Mari’s schoolmate Masato Kusaka.
Yuji has decided not to attack humans. Naoya is still trying to figure out what he wants. Yuka is trying to figure out Naoya. Naoya decides to be human and date. He drags Yuka out on a practice date.
Takumi, Mari, and Keitaro find Masato. As he and Takumi have a fencing battle, Mari’s former schoolmates are attacked by an Orphenoch. They go to rescue them. Masato follows and transforms using the Kaixa belt. He defeats the two Orphnochs.
==Plot==
After Masuda dies from using the Kaixa Gear, Mari, Takumi, and Keitaro begin looking for Mari's schoolmate Masato Kusaka. Yuji decides not to attack humans but Naoya is still trying to figure out what he wants. Mari finds Masato at fencing practice. Naoya decides to live as a human and takes Yuka out on a pretend date as practice for Mari. Masato and Takumi have a fencing battle as Mari's old schoolmates are attacked by Equisetum Orphenoch. Haruko is killed by the Crocodile Orphenoch. They go to rescue them, with Masato following and transforming into Kamen Rider Kaixa to defeat the Orphenochs.
==Cast==
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===Guest Cast===
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*Mari Sonoda (Child): 
*Masato Kusaka (Child): 
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*Office Clerk: 
*Student: , , , , 
*Gangs:, 
==Notes==
*As part of Super Hero Time, this episode aired alongside episode 10, .
*Viewership: 10.1%
==DVD releases==
Kamen Rider 555 Volume 4 features episodes 13-16: Friend or Foe?, Takumi's Spirit, The Fallen Idol ~ φ's vs. χ and Human Heart.
Blu-ray Box 1 comes with 17 episodes.
Category:Kamen Rider 555
Category:Episodes
Category:New Kamen Rider Episode