6 letter words:
buller8,
5 letter words:
bluer7,
brule7,
rubel7,
ruble7,
4 letter words:
bell6,
blue6,
blur6,
bull6,
burl6,
lube6,
rube6,
lure4,
rule4,
3 letter words:
bel5,
bru5,
bur5,
reb5,
rub5,
urb5,
ell3,
leu3,
lur3,
rue3,
ule3,
ure3,
2 letter words:
be4,
el2,
er2,
re2,
ur2,