Xvarts are tricky to devise tactics for, because their ability scores, their features and their Volo’s Guide to Monsters flavor text all seem to be at odds with one another. Their ability scores suggest Dexterity-focused sniping and shock attacks. Their Overbearing Pack feature suggests a reliance on shoving opponents prone, presumably to be followed up with melee attacks (both of which depend on Strength). And the flavor text states that they attack primarily to abduct, which implies grappling. There is a solution, but it’s tricky.
Xvarts move at the normal humanoid speed of 30 feet per round. Their Strength is low, and their Constitution merely average, so they’re anti-brutes—averse to melee slugfests. Xvarts will necessarily seek strength in numbers—and allies, specifically giant rats and giant bats. Giant rats make particularly good allies for xvarts, because of their Pack Tactics feature; giant bats, however, are tougher and more challenging. A xvart encounter should include, at a minimum, two xvarts per player character, plus an animal ally for every two xvarts.
Xvarts are neither smart nor wise. They have no ability to adapt if their favored strategy doesn’t work, and they may not be particularly quick to notice that it isn’t working. However, unlike the usual low-Wisdom monster, which waits too long to run away, xvarts are cowardly; if anything, they’ll run away prematurely from encounters that actually favor them. The Low Cunning feature gives them Disengage as a bonus action, but this represents instinctive evasive ability, not discipline. (more…)