use '?' for JOKER (blank)

From letters K, N, I, C, K, E, R, B, O, C, K, E, R  I made following words

13 letter words

knickerbocker[31]

10 letter words

knobkerrie[20]

8 letter words

beckoner[16], bickerer[16], cerebric[14], corncrib[14], reckoner[14], cicerone[12], croceine[12]

7 letter words

knocker[17], cockier[15], corkier[13], rockier[13], eccrine[11], cicoree[11], bicorne[11], cornice[11], crocein[11], crocine[11], coercer[11], enrober[9], cornier[9], onerier[7]

6 letter words

kicker[16], beckon[14], rebeck[14], bicker[14], cocker[14], recock[14], boccie[12], necker[12], nicker[12], broken[12], conker[12], reckon[12], broker[12], corker[12], recork[12], rocker[12], coerce[10], corbie[10], cicero[10], bicorn[10], bicron[10], kroner[10], boreen[8], enrobe[8], encore[8], bonier[8], coiner[8], orcein[8], recoin[8], briner[8], rebore[8], orbier[8], corrie[8], orrice[8], reborn[8], corner[8], ironer[6]

5 letter words

knock[15], brick[13], crick[13], brock[13], crock[13], bocce[11], bocci[11], boink[11], creek[11], biker[11], icker[11], brink[11], broke[11], ocker[11], conic[9], eikon[9], enoki[9], koine[9], rebec[9], recce[9], cerci[9], ceric[9], kerne[9], inker[9], reink[9], boric[9], croci[9], bronc[9], krone[9], niece[7], biner[7], brine[7], nicer[7], boner[7], borne[7], crone[7], recon[7], robin[7], orcin[7], brier[7], crier[7], ricer[7], borer[7], corer[7], crore[7], irone[5]

4 letter words

keck[14], kick[14], beck[12], keek[12], kike[12], kink[12], bock[12], cock[12], konk[12], kirk[12], bike[10], kibe[10], neck[10], nick[10], coke[10], bonk[10], knob[10], conk[10], nock[10], berk[10], kerb[10], reck[10], birk[10], rick[10], bork[10], cork[10], rock[10], bice[8], keen[8], knee[8], kine[8], keno[8], ikon[8], kino[8], oink[8], crib[8], reek[8], keir[8], kier[8], kern[8], kirn[8], rink[8], croc[8], kore[8], been[6], bene[6], bine[6], cine[6], nice[6], bone[6], ebon[6], cone[6], once[6], cion[6], coin[6], coni[6], icon[6], beer[6], bree[6], cere[6], bier[6], brie[6], cire[6], rice[6], bren[6], brin[6], bore[6], robe[6], cero[6], core[6], biro[6], brio[6], coir[6], born[6], corn[6], birr[6], erne[4], rein[4], inro[4], iron[4], noir[4], nori[4]

3 letter words

ick[9], eek[7], eke[7], ken[7], bee[5], cee[5], ice[5], ben[5], neb[5], bin[5], nib[5], nee[3]