Go to Falconreach, and proceed down, after that go to Falcons Nest.

Go to the statue and press on " Wrath of Xan"

Choose " Face Xans wrath"

Then after you have a chance to own Xan!

Edit: You can also face him during the Other Quests -> Save Lymcrest chain in Warlic's zone.

According to SOWPODS (the combination of Scrabble dictionaries used around the world) there are 1 words with the pattern ---XANS. That is, seven letter words with 4th letter X and 5th letter A and 6th letter N and 7th letter S. In alphabetical order, they are:

dioxans

Xanax stays in your system 3-7 days depending on your metabolism, body weight and other factors.
Xanax stays in your system 3-7 days depending on your metabolism, body weight and other factors.

There is no such thing as "a drug test". There are dozens (really, potentially millions) of drug tests, each of which looks for a specific molecule or closely related family of molecules. If one of the molecules being tested for is the one you personally abuse, then yes, it will "come up". If not, then it will not.

There's usually very little point in screening for drugs that are not commonly abused. Things like opiates, marijuana, alcohol, meth ... it's pretty common for any given drug screening to include those. Less popular drugs generally aren't checked for unless the person doing the checking has a specific reason to believe that the person being tested may have used one of them.