Loki did not know what they were protecting but it must be something fragile for them to program the door to be destroyed in the way that it did.
The dust settles.
there is a long straight narrow path leading toward a wide rotunda hall. Loki close his eyes as he turns into green mist again and then then appears inside that round hall.
And then when he opens his eyes, he was shocked.
'Hah' he exclaims to himself. There is a trace of regret and sadness in his voice. It was almost like his voice is trembling.
Now he understands why, they were both eager to run.
Why Nathan could give up his life so willingly and why Riana was so insistent in wanting to resist him
He was suddenly reminded of the past where he had brought Riana to Greece and he sighed.
'No wonder' he said to himself as he looks at the precious treasure that Riana and Nathan had hidden.