It's a flying brick

Looking properly around the fortress there are three buildings, a one story building that was the stable.  A two story building that held barracks and food storage. A three story building that on top of had controls panel. Much of the fortress was destroyed in the attack and take over. Most of it caused by the dragon.  Isaac, Jessica and Rekka looked over the control panel while the other looked around what could become their new home. Ajara went into the barracks in hopes of finding food. Cortanna looked around the stables.

There were five buttons and two switches.Of course none of them were labeled in any language but in pictogram. Isaac studied it for a moment before pressing one of the buttons. (the second one down) A sound happened but nothing else. Pressing another, (the last one) the fortress began to sink. Ajara who was, at the time, looking around in the barracks freaked out when the ceiling start to go down. She ran out of the building and began to shout at Isaac but there was nothing he could do. Slowly the building continued to sink into the ground. everyone made their way to the top of the three story building, and the control panel.  Once all the building where under the surface it slow began to raise up.  The broken walls and building were once more rebuilt and made like new.  Isaac made note of what that button did, and moved on to the next, the Fourth button from the top. This time the fortress shot up and with blinding speed flew straight into the side of the mountain. Knocking everyone to the ground or into the side of a building, badly hurting everyone. Quickly he press the button again the fortress halted. After some healing and choice words, Isaac pressed the second button once more. this time a similar sound happened and a wavy bubble surrounded the fortress.  making note of that, he pressed the first button. once again the fortress sank into the ground. Unlike the time before the contorl panel and everyone else went with it. Ajara, using her wings flew up, to keep from being sucked under the ground but the protective force field stopped her from getting getting out. Once everything was underground it stopped. Rekka might at one point thought this strange but it just seem the norm now. Isaac pressed the the button again and the fortress raised from the ground.
  All that was left was two buttons. From what Isaac guess he press the fifth button with confidence. Once again the fortress started to change, this time, shrinking until all that was left of it was a miniature size that would easily fit in a pocket. Isaac picked it up and looked at it. then he placed it back on the ground and as if commanded began to return to it's normal size.  By this time everyone was tired from the ever changing fortress, but now it was know what it could do. With a last press of the last button the fortress shakily floated off the ground. Using the switches, Isaac moved the right one forward while, keeping the the left one in the middle. Slow, every slowly, the fortress moved forward.
"Wow," Rekaa said sarcastically, "We are really moving now? I can walk faster than this."
 But she was soon eating those word, for the fortress picked up speed. Soon they were going faster than any of them could fly or run. "Just don't crash us again." Rekka said.