Hello everyone, nice to welcome you on our site, this page even has Level 15 answers. I enjoy it =D
Level 15 - SISNENG
The answer to this puzzle is:
Words: ENSIGNS, GNEISS, SINGES, SENGI, SINES, SEGNI, NINES, INNS, SEIS, GIEN, EGIS, ENGS, SINE, GIES, GINS, NESS, SINS, GENS, SIS, GEN, GIN, SEN, INS, ENG
Bonus words:
ENSIGNS, GNEISS, SINGES, SENGI, SINES, SEGNI, NINES, INNS, SEIS, GIEN, EGIS, ENGS, SINE, GIES, GINS, NESS, SINS, GENS, SIS, GEN, GIN, SEN, INS, ENG