Biddleybong is Constantine's "superior brandy" which he offers to Garrett in the cutscene following the TDP/TG mission "The Sword". Oddly enough, Garrett fails to take notice of the deep-green hue and unusual consistency, but drains it at a gulp at the conclusion of their meeting.
The spilled drink is not seen by Garrett to be sprouting into grassy stems and roots. The drink itself did not seem to affect Garrett in any way. It is unknown if this is a natural property of the drink, or if it has been modified by Constantine or Viktoria in any way.
Label[]
Though difficult to make out, the full label reads:
"Biddleybong
A potent and invigorating cognac
aged in greenwood casks
Bottled at Centauri Vineyards, New Hope"
Trivia[]
The label indicates that it was bottled at the Centauri Vineyards, New Hope. This is a nod to one of LGS' previous games, Terra Nova: Strike Force Centauri.