A is for Abyss, from whence demons hail.
B is for Bards, the spinners of tales.
C is for Cleric, please heal me now!
D is for Dark elves, whose name rhymes with cow.
E is for Erathis, may she bless our field.
F is for Fighter, the plated meat shield.
G is for Golem, matter made an'mate.
H is for Hags, who atroc'ties commit.
I is for Iggwilv, who writes tainted prose.
J is for Jocks, the players' worst foes.
K is for Kraken, unleash it, I say!
L is for Leomund, in his tiny hut stay.
M is for Modrons, they're law's strangest friend.
N is for Never, when edition wars end.
O is for Orc, pig-men with rabies.
P is for Paladins, who may kill orc babies.
Q is for Quasits, who tempt you with perks.
R is for Rogue, the class played by jerks.
S is for Sharn, the City of Towers
T is for Tarrasque, the whole world it scours.
U is for Underdark, where all caves must flow.
V is for Vargouille, hey, where'd my head go?
W is for Wizards, our lords from the coast
X is for Xorn, from the plane of Earth most
Y is for Yellow, a poisonous mold
Z is for Zombie, who never grows old
Fun fact: You can substitute "Vorpal" for "Vargouille" without changing the line!