"Ah, I see you caught the result of one of my latest experiments. I really thought I had cleaned up better." replied Travis as he examined himself an any more traces of soot, "I'm sure you're familiar with runic spells, are you? I've recent came into possession of a tome detailing the ancient knowledge of writing runes. Interesting stuff, though I'm afraid many of the alchemists at the time were not familiar with modern science." 

Just as he finished, Travis reached over to his portable trunk and sat is flat across his lap. The chest itself was not too terribly cumbersome for its size but was surprisingly relatively light. Pressing his thumbs against two ports of the central lock, Travis divulged slight portion of his mana into the lock which unlocked in response, swinging its smooth rounded cover upwards. Within the opened chest was a shroud of blackness, devoid of any shred of light and masking its true depth. Travis dipped his entire right arm into the carry-on abyss, betraying the chest's flat height in comparison to his arm. He soon retracted his right arm and within his hand was a small clear case with a small parchment of a rune printed onto it. 

"Here, have a look-see." said Travis, offering the small case to Yuno to examine, "I have the rune confines as it is, apparently, very sensitive to mana - in fact, it doesn't take any large amounts of it to even cast. The rune itself creates a combustible by-product of heated gases ignites once it comes in contact with oxygen. The resulting explosion, as you can see, was much more powerful than I anticipated but very mana-effecient at the same time. I created it as a means of a plausible getaway countermeasure and as a creative trial using old methods and current knowledge.

Seeing another patch of soot, he quickly brushed the dusty stain from his shoulder, "...But I suppose it would be perhaps a bit, overkill."