guot, good,beȥȥer, beȥȥest, beste (23]).
übel, bad,wirser, wirsest, wir(se)ste.
lützel, little,minner, minre (9, 3]), minnest, min(ne)ste.
michel, great,mērer, mēr(r)e, meiste.

[§ 59.] The following adjectives are defective:—

ērer, ērre, ërre, former,ērest, ērste, first.
hinder, hinder,hinderste, hindmost.
ober, upper,oberste, uppermost.
leȥȥeste, leste (23]), last.
vorder, former,vorderste, foremost.
C. Formation of Adverbs from Adjectives.

[§ 60.] [1.] By adding -e (= OHG. -o) to the adjective when this does not already end in -e, as ëben, even, hōch, high, lanc, long: adv. ëbene, hōhe, lange; edele (OHG. edili), noble, übel (OHG. ubil), evil: adv. edele (OHG. edilo), übele (OHG. ubilo).

[2.] Dissyllabic adjectives ending in -e and containing a mutated stem-vowel change it to the corresponding unmutated vowel, when used as adverbs, as schœne (OHG. scōni), beautiful, herte, hard, senfte, soft, süeȥe, sweet, swære, heavy: adv. schōne, harte, sanfte, suoȥe, swāre.

[3.] By adding -līche or -līchen to the adjective, as ganz, whole, vlīȥec, diligent: adv. ganzlīche(n), vlīȥeclīche(n).

[4.] The comparative and superlative degrees of adverbs are the same as the corresponding uninflected forms of the adjectives without umlaut:—

Adjectivelanc, longlengerlengest.
Adverblangelanger
(OHG. langōr)
langest
(OHG. langōst).

[§ 61.] The following are irregular:—