8 letter words:
grubbers13,
7 letter words:
grubber12,
rubbers11,
burgers10,
6 letter words:
rubber10,
burger9,
geburs9,
regurs7,
surger7,
urgers7,
5 letter words:
burbs9,
bergs8,
burgs8,
gebur8,
grubs8,
brers7,
burrs7,
burse7,
rebus7,
rubes7,
suber7,
grues6,
regur6,
surge6,
urger6,
urges6,
ruers5,
surer5,
4 letter words:
bubs8,
burb8,
ebbs8,
begs7,
berg7,
bugs7,
burg7,
grub7,
gubs7,
brer6,
brus6,
burr6,
burs6,
rebs6,
rube6,
rubs6,
urbs6,
ergs5,
grue5,
gues5,
gurs5,
regs5,
rugs5,
urge5,
errs4,
ruer4,
rues4,
ruse4,
serr4,
suer4,
sure4,
ures4,
user4,
3 letter words:
bub7,
ebb7,
beg6,
bug6,
gub6,
bes5,
brr5,
bru5,
bur5,
bus5,
reb5,
rub5,
sub5,
urb5,
erg4,
gue4,
gur4,
gus4,
reg4,
rug4,
seg4,
ugs4,
err3,
ers3,
res3,
rue3,
ser3,
sue3,
sur3,
ure3,
use3,
2 letter words:
be4,
gu3,
ug3,
er2,
es2,
re2,
ur2,
us2,