Too late.
They are all just a moment too late.
Fugaku, the only one who could have helped, feels the tug of the rinne-summon at the worst possible time. The final wave of reinforcements is calling for him to be on standby, meaning Fugaku cannot move until they arrive. Minato is too far away - a problem that only exists because he apparently did not think to mark Iruka for the Flying Thunder God Jutsu. Akatsuki are all busy, as are the other defenders. Naruto and Sasuke are high in the air, safe. Konan is desperately trying to get past the Second Mizukage, who is blocking her from assisting Iruka again.
And Iruka is about to die.
The moment he moves or activates his chakra, Fugaku will effectively call the third wave of reinforcements. They will hinder rather than help the situation, simply by delaying any action Fugaku could take. Is there anything, anything at all that he can do? Fugaku nearly panics as he watches Kohari Umino kick her son into a pile of rubble and activate the Wrath of Jashin seal. Fire bursts out of the seal.
"Water Style, Water Prison Jutsu!" Fugaku hears a familiar voice say. A Water Prison forms, not around Kohari, but around Iruka. The torrent of fire engulfs the ball of water.
Two Mist ninjas, one young and one middle aged, attack Kohari from either side. The young ninja attacks with the ninja blade Hiramekarei while the older ninja simply attempts to punch Kohari. Both miss their mark when Kohari leaps high into the air. Fugaku has heard rumors of Kohari's ability so it does not surprise him in the least that she maintains the Wrath of Jashin Seal as she leaps away, lands behind the younger Mist ninja and raises her hand in a half ram seal, ready to cast another jutsu.
"Lava Style: Lava Dragon!" Fugaku sees Mei Terumi, the one who cast the Water Prison jutsu, standing nearby. Iruka is lying, soaking wet, at Mei's feet. Fugaku cannot tell if Iruka is dead or alive. Mei spits the lava dragon out of her mouth. The Dragon roars and flies towards Kohari, engulfing her in a second.
The Wrath of Jashin Seal deactivates and vanishes.
Obito appears beside Fugaku. "Lord Hokage, where is the third group of reinforcements from the Leaf? As soon as they arrive, I am going to get Jiraiya."
Fugaku blinks in surprise. "You could've gone and gotten Jiraiya this whole time? What stopped you?"
"Before you arrived with reinforcements, the defence at the Temple was too weak," explains Obito. "And sensei seemed to be doing a good job of teaching Naruto and Sasuke, so I didn't think it was urgent I get Jiraiya."
Something occurs to Fugaku. "And how exactly are you actually going to find Jiraiya?" he asks. The third wave still has him on standby. What is stopping them from coming? They are past overdue!
"I can place a mark on any person or place I want to be able to get to quickly," says Obito. "Then I can travel to them with my kamui whenever I want. I placed a mark on all the village leaders Akatsuki is allied with, every member of Akatsuki, Jiraiya and my kid. I also have markers in several places in each Hidden Village I've been to, as well as on most landmarks and important monuments outside village borders."
"Does Jiraiya know you have a marker on him?" asks Fugaku sceptically.
"Yes he does," says Obito. "I asked him to let me mark him as a precaution."
"Hang on one second," says Fugaku. He is sick of waiting. Channeling his voice through the chakra rod in his hand, Fugaku says, "Hurry your asses up, will you?"
Shisui's reply causes Fugaku to facepalm and groan.
"Just tell Tenzou to send a clone to give the kids to Kazama!" Fugaku snaps. "We need you all here five minutes ago!" Fugaku waits a few seconds for Shisui to relay the message and get everyone to grab the chakra rod. The moment he receives the signal the Third Wave is ready, Fugaku summons them to the Temple of Jashin.
With a poof, Shisui's Third Wave appears. Shisui managed to bring the Third Hokage, along with Inoichi, Chouza, Shikaku, Might Gai, Lady Tsunade and Tenzou.
"The Third Wave is here, get going Obito," says Fugaku, forgetting that the most recent arrivals at the Temple don't know who Rain is.
"Wait, don't…" Obito starts to say.
Kakashi interrupts him, saying, "You might as well ditch the mask, Obito. The secret's out." Then Kakashi sees Tenzou. He grins widely and adds, "Oh hey, Tenzou! Come over here and meet my Dad."
Obito, who is taking off his mask, glances over to see the White Fang, in all his reanimated glory. Obito's face lights up. "OOOOOOOO!" All he can manage to vocalize is an excited noise.
"GO!" snaps Fugaku, sensing another delay in getting reinforcements. "We need Jiraiya here!"
Obito's face falls. He points at Sakumo. "But my hero!" he wines. "My role model…"
Fugaku wacks Obito over the ear. "Get going!"
"Yes, Lord Hokage." Obito vanishes in a swirl, a pout on his scarred face.
"Lady Tsunade," says Fugaku, turning to the new arrivals. "I am glad you are here. Go take a look at Iruka."
Tsunade heads over to Iruka and crouches down beside him.
"Is he alive?" asks Mei, before Tsunade can even check.
Tsunade checks and confirms that Iruka is, indeed alive.
"Oh, thank goodness," says Kohari, her relief momentarily breaking through the jutsu caster's control. "I don't know who you are, Lady, but thank you for stopping me from killing Iruka."
"Didn't I kill you?" asks Mei, mildly surprised.
"Oh, I'm a reanimation," says Kohari cheerfully. "I'm already dead. Please don't take it to heart when I try to kill you: I am being controlled." And with that, Kohari unleashes a volley of shuriken, sets the shuriken on fire and vanishes in a puff of smoke. Mei dodges the shuriken, only for Kohari to appear above her and kick her in the face. Mei blocks the kick with her arm.
Glad that Mei is able to hold her own against Kohari, Fugaku takes a quick look around the battlefield to make sure the other reanimations are being kept busy. They are: all of the reanimations are busy fighting either members of Akatsuki or other reinforcements. Zetsu is still fighting the first two Hokages.
Where are Naruto and Sasuke? Fugaku looks up to see if they are still high in the sky. They are up there, alright. Sasuke is clinging to Naruto's back like her life depends on it - which it probably does.
"Minato!" Fugaku calls to the Fourth Hokage. Where did he go?
One of Minato's special kunai appears beside Fugaku. A second later, Minato himself appears with Might Dai close behind. "Little busy right now!" Minato says.
Kisame and Kakuzu attack Dai from either side.
"We will handle this one," says Kakuzu. "The woman fighting Mito Uzumaki needs assistance."
"Minato, go help your wife," orders Fugaku. "I will protect Naruto and Sasuke."
In the Kamui world, Obito takes a deep breath and sighs. The White Fang was reanimated. Obito is both pleased and angry. Pleased that he has a chance to meet his childhood hero, and angry that The White Fang was dishonoured in such a way. Spurred by these conflicting feelings, Obito follows the marker he put on Jiraiya and exits the Kamui world.
Obito yelps and covers his eyes.
"I did warn you," says Jiraiya, laughing.
"Oh my," says the woman in bed with Jiraiya. "How did he get in here?"
"Just finish up," says Obito, running from the hotel bedroom. "I'll be outside waiting." Obito slams the door behind him and leans on the wall, his eyes wide. Jiraiya did, in fact, warn him about that.
"Obito," he'd said. "Bear in mind that if you ever go looking for me through your jutsu, you might walk in on me having sex."
Obito momentarily forgets how urgent getting Jiraiya to the Temple of Jashin is. He remembers when Jiraiya exits the room about a couple of minutes later tying his scroll onto his back. "That was fast," says Obito, wide eyed.
"We were finishing up anyway," says Jiraiya. "Now what was so important you interrupted my sex life?"
"The Temple of Jashin is under attack," says Obito, transporting them both into the Kamui world. "Zetsu broke through the barrier and he has an army with him."
Jiraiya's face turns grave. "Then why did you leave?"
"We managed to get some reinforcements," says Obito. He does not want to say more - they need to get back to the temple. Obito transports them out of the Kamui world, back to the Temple of Jashin and back to the chaos.
"JIRAIYA SENSEI!" Minato sensei yells, waving to Jiraiya.
"Minato?" says Jiraiya, gobsmacked. "KUSHINA? HOW? WHAT? WHY? WHEN?"
"Naruto is a Grand Master of Fuuinjutsu now," says Kakashi smugly. As he says it, Kakashi ducks under his father's sword to avoid losing a head.
"Jiraiya, stop gawking and help Nagato defeat Ikkaku's reanimation!" orders Lord Fugaku, pointing to where Ikkaku Umino is close to defeating Nagato.
"Yes Lord Hokage," says Jiraiya and heads into the battlefield to do just that.