Gearbox basically put Duke Nukem into a re-release of Bulletstorm. More info here.

Redeem below codes here on GoG.  Did you miss out on unused codes? E-mail yatta@duke4.net.

Duke Nukem 3D:

2CTW-HMQJ-K42M-DQYR
ZRX6-VQRK-3AJE-CW82
6JGR-QXFN-3LXW-9PQY
JJH6-93T2-VETB-6U9G
465R-SCM7-5522-XYJ8
LF9J-EHUJ-8VTV-WXAD
QQDN-97CT-E9AP-8HGS
R4NJ-NKYK-TSYJ-HYYG
NCCN-HMDB-66T5-7N77
MTBZ-ECLK-ZH6J-W6MK

Shadow Warrior Classic Complete:

CB5AA-C4B62-4218F-31BB8
3F6B8-5B9E9-665E5-B245E
9736B-95A91-54FC1-74FD8
526AF-B4CB3-A698E-1F473
DFD83-F39C8-1E6B4-9FEE5
25BF8-3994B-A776A-3E3C3
64711-6A74F-292C3-F5CDF
82655-37DD7-38D4F-D885F
74AC1-BF5A7-46A9F-4CEC9
8AE36-4741F-C224A-9A885

Redeem above codes here on GoG.  Did you miss out on unused codes? E-mail yatta@duke4.net.