Tempest Shadow had returned to the Crystal Empire expected to resume her training to become Twilight Sparkle's royal guard captain. Instead, she had returned to an empire on the verge of an attack by it's most feared enemy. Like Shining Armor had told her, Tempest wasn't going to still be fully welcomed, but there was very little choice.

"To be honest," sighed Princess Cadence, as she looked out among her kingdom's fighting force taking up positions at the edge of the empire's borders. "I haven't seen the Crystal Empire like this since Thorax first came here. If only we could…"

"We can't, Cadence," sighed Shining Armor, looking over at his wife. "We have to focus on what's going on right here and right now. It's clear to me that Sombra will be attacking in all directions, so we're going to want every inch of this kingdom covered."

Shining Armor then turned his attention over to Quill, Drax and Groot thinking that they could be some help.

"Star-Lord, can you and your friends help defend our kingdom?" he asked.

"Well, we aren't quite 100% after our freefall, but we'll do what we can to help," answered Quill, reaching into his pocket and touching his blaster. "Normally, we get rewarded and…"

But a look from Drax interrupted him.

"Let's not think about rewards right now, Quill," he remarked. "We focus on protecting the empire."

Just then, a messenger pony came running to them with a message in his aura. Shining Armor read it carefully before passing it over to Cadence.

"What is it?" asked Drax.

"There's a platoon of about 300 troops heading our way," answered Shining Armor. "They are a combination of Sombra's forces and Grogar's forces. And guess who's leading them?"

"Sombra?" asked Cadence, nervously.

"Oh yeah," said Shining Armor, immediately putting on his battle helmet.

…

From inside the throne room at Tambeleon, Grogar watched with Tirek, Cozy Glow, Chrysalis and the Storm King as his combined forces marched towards the Crystal Empire.

"I just hope Sombra knows what he is doing," said Cozy Glow. "Do you think it is a good idea for him to just jump into the action?"

"Patience, my child," replied Grogar, looking over at his viewing globe. "I tried to talk Sombra out of it, but he wouldn't listen."

"Then why didn't you stop him?" wondered the Storm King. "Going in without backup is…uncool."

"Because he'll learn something on his own, that's why."

Watching from the viewing globe, the villains saw the overthrown king of the Crystal Empire led his combined forces towards the borders of the Crystal Empire.

"Soon, my Crystal Slaves," he laughed evilly. "You will be mine once again."

…

Meanwhile, Rocket Raccoon and the remaining Guardians found themselves witnessing Crystal ponies running all around them, preparing for the impending assault.

"Something doesn't seem right," cried Gamora, climbing out of bed with some of her strength back. "Why is everyone running around like crazy?"

"Because there is an attack coming?" guessed Rocket.

"Something is coming," advised Mantis, her antennae picking up movement coming from Sombra's forces. "The Empire is on edge."

Realizing that they needed to act fast, Rocket, Gamora and Mantis each got out and attempted to make their way to the front lines. The bounty hunter raccoon struggled to walk, but wasn't going to back down easily.

From up in the tower, the rulers of the Crystal Empire along with Tempest Shadow had all of their horns ready and aimed at the approaching forces.

"Princess Cadence," cried Sunburst, running over to them. "I've placed Flurry Heart in the shelter."

"Thank you, Sunburst," replied Shining Armor. "Go and stay with her until we give the all clear."

Knowing that their daughter was safe, Shining Armor and Cadence focused on the battle at hand. Just then, a guardspony cried out in a loud voice:

"SOMBRA, RIGHT AHEAD!"

Without any more warning, the view of King Sombra leading a platoon of donkeys and ponies loyal to him appeared over the horizon, ready to charge and seize the empire. Quill donned his mask and Drax pulled out his knives while Groot readied his vines.

"Steady!" Shining Armor shouted. "Wait till I give the order!"

The Crystal Empire's military readied their horns as Sombra's forces got nearer and nearer to the borders. As they neared the empire, Shining Armor turned to Tempest.

"Consider this part of your training," he said and Tempest nodded in reply. She knew Shining Armor had a point, this was more than likely a training exercise for the real deal. Soon, the combined forces were about a mile from reaching the borders. Raising his hoof and lowering down sharply, Shining Armor gave the signal. "COMMENCE FIRING!"

Acting on his order, the Crystal Empire's guardsponies opened fire on the advancing army, randomly striking down wayward soldiers. Snarling, Sombra charged and powering up his horn, prepared to storm through anypony that stood in his way. From up in the tower, Shining Armor and Cadence fired their magic blasts as well while Quill did the same from his blasters. At that moment, Rocket and the remaining Guardians made their way up.

"What's going on, Quill?" Rocket cried.

"You guys planning to help?" Quill asked, handing Gamora one of his blasters. Joining the ranks, the remaining Guardians fired upon the charging forces. Sombra used a shield spell to deflect whatever blasts were fired upon him.

"DON'T LET HIM PASS!" shouted Cadence, who was just about to fly down, only to be stopped by Shining Armor. "SHINING ARMOR, WHAT ARE YOU DOING?"

"I can't let you go down," he ordered.

"WHY?"

"He wants your magic," Tempest said, firing blasts from her horn as she stepped onto the ledge of the tower. "For Emperor Grogar to use for his own free will."

With a loud yell, Tempest Shadow jumped off of the ledge and ran through the streets right towards Sombra. Seeing this act of bravery, Quill realized that Tempest needed support.

"We've got to help her, who's with me?" he asked his fellow Guardians and all except Gamora and Mantis, jumped down to help Tempest stop Sombra from entering.

…

At S.M.I.L.E. headquarters, news of the impending attack on the Crystal Empire reached Fury Swipes.

"What's going on?" the human-like cat cried, trying to look at the map of Equestria. "Sombra's on the move?"

"Afraid so, sir," said a S.M.I.L.E. agent. "He has an army of 300 ponies loyal to him as well Grogar's donkey soldiers."

"Get me the princesses," he ordered. "I want them to know what is happening here."

But like Cozy Glow in Tambeleon, Fury Swipes was also wondering how and why Sombra was attacking alone. To him, it just didn't make any sense.

…

Still, news of the impending attack reached Twilight's castle and the Princess of Friendship, fearing for her brother, sister-in-law and niece knew she needed to help.

"Twilight, what is it?" cried Spike as Twilight dashed out of her office.

"It's the Crystal Empire," Twilight replied. "Sombra's attacking it."

"But I thought Cadence destroyed him."

"Thank Grogar for bringing him back to life," Twilight said as she quickly took to the air. "I'll report when I can!"

Spike then watched as Dr. Strange and Bruce Banner followed with Bruce slowly transforming into the Hulk.

"Feels good to let it out, Dr. Banner?" the wizard remarked.

"Yeah, this has been going on for too long," snarled the changing Bruce.

From the window of one of their classrooms, Peter and Rachel watched Twilight take to the air during one of Rainbow Dash's loyalty classes.

"Um, excuse me, guys?" asked Rainbow Dash, trying to gain their attention. "Pay attention here, will you?"

Sooner or later, Peter knew that Spider Man was going to have to make an appearance somewhat…