Summary: All of them believed that Tony Stark was only the brain of the avengers, their consultant, their mechanic. But they were all wrong. He is their heart. Their most precious. They would do anything for him . Even destroy the whole universe just to avenged the death of their heart.

The avengers was once called the defender of the earth was now the feared destroyer of the universe.

Sierra stared at the ruins of what was once a beautiful and lively city of New York. It was nothing now but destroyed buildings, abandoned shops, and empty streets.

It wasn't just New York but the whole country and the other countries who dared cross them.

The only one left standing was the avengers tower. But even this doesn't look and feel the same anymore. Not since the death of the tower and avengers heart; Anthony Stark-Rogers.

What was once a tower that was buzzing with activities was now very quiet and empty. No one stay here anymore aside from their family. They would never abandon this tower. Their home. The place where they build happy memories together with their papa.

It'a been six years now since his untimely death. But the ache she and the rest of them felt was still as painful as before. They said that time heal wounds and the pain would eventually fade away but they were all wrong.

As time went by, the pain only intensified as well as the rage and hatred they all felt towards those who murdered their papa and shattered the heart of their family.

"Sierra," a hesitant voice behind her pulled her away from her depressing thoughts. Turning around she saw her twin together with their uncle loki and uncle stephen. Her twin held out the tiny orb that they had work for several months. He look worried and terrified. And she couldn't blame him. She also felt the same. This was their only chance to save their family and to prevent the destruction of the universe.

She look at their uncle who both look grim and exhausted. They've use all their magic to make that device that would bring them back to the past. She knew both of them still felt guilty for not being able to prevent their papa's death. But she couldn't blame them. It was all of a sudden. No one expected for it to happen. And even after that uncle Loki tried to bring their papa back. He went to Hela. But the Goddess wouldn't allow it. Saying that it was their papa's fate. And that there's a reason why everything had to happen.

But before uncle Loki left Hela gave them an orb and said that it would help us. It took them months to undestand how to use it. And here they are now trying it for the first time and hoping that it would work. They needed to do this now before their dad return and found out what they were about to do. They didn't inform their dad about their plan not wanting to get his hope up and be devastated once again when it doesn't work.

They knew their dad missed their papa so much already. At times they felt that he wanted to just end it all, to just give up just to be with their papa once again. But then he would look at her and Ciaran and he would be determined again to continue for her and Ciaran the only thing left of papa. And beside, papa's murderer wasn't found yet. He wouldn't give up, not until papa was avenge.

Don't worry Ci everythings gonna be alright," she whispered softly hugging both their uncle one last time and casting one last glance to their home hoping to God that the next time she saw this it would be filled with laughter and happy faces once again.

Taking a deep breath she placed her hand above her twin above the small small orb that would take them to the past. She saw both Loki and Stephen cast all their magic towards the orb they're holding With a flash they were engulfed with a blinding light then they were gone.

Bruce watched with barely concealed amusement as Tony slumped into the couch pouting. Their beloved genius had been sulking for over an hour now since his boyfriend Steve and the rest of the team left when Fury called them.

Unknown to Tony, the team was still in the tower preparing for a surprise party for his thirtieth birthday and his and Steve third year anniversary and also Steve will finally Propose.

'' Tony-'' he started but was cut off when a strange ball of light suddenly appear behind Tony his eyes widen in horror when the said ball of light started to turn bigger and wider. Without a second thought he immediately tackled Tony to the floor just in time for the unknown object to explode destroying half of the workshop. It's a good thing that he managed to cover Tony with his body or else he would be dead by now with how huge the explosion was.

When he was sure that there was no more danger to follow he immediately check on Tony and his eyes slowly turn green in rage and worry when he saw that Tony was unconscious much more when he noticed a lot of blood seeping from Tony's head.

He immediately demanded for JARVIS to contact Loki who wasn't in the tower at the moment. He quickly applied a first aid on Tony while waiting for Loki and the others who surely heard the explosion. He was so focus on Tony that he didn't notice the two figure approach them not until one of them suddenly burst out crying.

Bruce immediately place himself between Tony and the stranger and was shocked when he saw two teenager in front of him. The boy was the one who was crying trying to come closer to Tony while the girl held the boy stopping him from approaching them.

" Sierra, let go of me. Papa, I want my papa. Please erra. I want my papa," the boy cried out mournfully as he struggled to be realease by the girl holding him.

" Calm down Ci," Sierra whispered to her twin as she hugged him tightly. She understand Ciaran's reaction. Between the two of them Ciaran is much closer to their papa. Not that she wasn't close to their papa too but Ciaran like their papa is a child genius he love to invent and spent all his day in their papa's lab. While she like their dad much prefer her arts.

Out of nowhere Loki suddenly appeared in the lab and immediately crouched down beside Tony and started healing him not paying any attention to the others in the room. At the same time the elevator door opened the other avengers rushing inside the destroyed lab.

********

Floors above them Steve and the rest of their team was startled by the loud explosion and was immediately on their feet rushing towards Tony's
workshop. All of them were dreading what they would found there.

Steve sighed in relief when the elevator door open immediately for them. It only means that the tower isn't under attacked.

"JARVIS, what happened?" he asked immediately as soon as they were all inside.

"There was an unknown object that suddenly appear in the workshop that had caused the explosion, Captain. manage to cover sir to keep him safe just in time," the AI informed them much to their relief. It is a good thing Bruce insisted in staying with Tony than leaving the young genius alone in his lab.

As soon as the elevator door opened they all immediately rushed inside.

Using this as a destruction Ciaran manage to free himself and without any word before Sierra could stop him he immediately rushed towards Steve

"Dad!" with an anguished cry he launched himself to their dad and hugged him tightly. The others were too shocked to do anything as they stared at the boy clinging to Steve and to the girl who was looking at them all longingly her eyes filled with unshed tears.