yucas uycas ycuas cyuas ucyas cuyas yuacs uyacs yaucs ayucs uaycs auycs ycaus cyaus yacus aycus cayus acyus ucays cuays uacys aucys cauys acuys yucsa uycsa ycusa cyusa ucysa cuysa yusca uysca ysuca syuca usyca suyca ycsua cysua yscua sycua csyua scyua ucsya cusya uscya sucya csuya scuya yuasc uyasc yausc ayusc uaysc auysc yusac uysac ysuac syuac usyac suyac yasuc aysuc ysauc syauc asyuc sayuc uasyc ausyc usayc suayc asuyc sauyc ycasu cyasu yacsu aycsu caysu acysu ycsau cysau yscau sycau csyau scyau yascu ayscu ysacu syacu asycu saycu casyu acsyu csayu scayu ascyu sacyu ucasy cuasy uacsy aucsy causy acusy ucsay cusay uscay sucay csuay scuay uascy auscy usacy suacy asucy saucy casuy acsuy csauy scauy ascuy sacuy
Note: these 'words' (valid or invalid) are all the permutations of the word yucas. These words are obtained by scrambling the letters in yucas.