Serious Sam 4 (55% discount)
https://www.gog.com/redeem/RYZR049E555347ACF0

Serious Sam: The First Encounter
Serious Sam: The Second Encounter
Serious Sam's Bogus Detour
85% discount
https://www.gog.com/redeem/966E04A1792E381312

hitman series bundle 85% off, expires on Aug 8, 2021, 2:59 PM european time

*64050904147A

* = HITMAN

Serious Sam: The First Encounter, Serious Sam: The Second Encounter, Serious Sam's Bogus Detour
966E1F224EED1A9A86

Serious Sam 4
RYZR1F15135E641DAC

They actually made that one available to everyone...it's on the front page near the top.
(also some small kudos to GOG for finally making a code available to those who don't use the newsletters)

thats odd, why didn't they just made a bundle sale. so is the promo code the same for everyone or is it individual?

The code is listed in the banner on the front page, so it seems to be for everyone. My guess is they perhaps want to appear to be listening to the complaints about such codes being tied to newsletters.

Serious Sam 4 discount - code: RYZR8B8492C2670gog405
Serious Sam first 3 games discount - code: 966E8B8E5F75165gog418
If you want to use discount, remove @gog@ from codes above.

Discount on Serious Sam games.
SS 4 base game code: RYZR90FCD931C___93070
Previous SS games: 966E91061FC90___EA8FA

To redeem this discounts remove "___" section.

Serious Sam: The First Encounter + Serious Sam: The Second Encounter + Serious Sam's Bogus Detour (-85%)
https://www.gog.com/redeem/966EGOG2302B81BA232GOG7C

Serious Sam 4 (-55%)
https://www.gog.com/redeem/RYZRGOG22F51ADGOG8621377

[remove all the GOG intercalations]

Codes expire on Aug 8, 2021, 1:00 PM (UTC).

GOG Newsletter Discount - Serious Sam Series
-
Serious Sam 4

RYZR2D319B0F7D9FDEgog
-
Serious Sam: The First Encounter + Serious Sam: The Second Encounter + Serious Sam's Bogus Detour

966E2D3C6AEB93F090gog
-
[Note: Remove the word "gog" from the code]
-
The offer ends on 8th August 2021, at 1 PM UTC.
.

Another code for Serious Sam 4, expires on 8th August 2021, at 1 PM UTC.

RYZRsam83A0E58sam984F212

There are 2 many sam in the code, remove them.

A code for 80% off Mad Max

7QW8349B8F8606334AXXX
(Remove XXX)

The offer ends on 15th August 2021, at 1 PM UTC.

Remove the water from the code below for another 80% discount off of Mad Max.


7QW85DCA06waterD9E80BE1

Mad Max 80% Discount code:
https://www.gog.com/redeem/7QW8C1BCF81FAF464gogC

Remove "gog" from the code

The offer ends on 15th August 2021, at 1 PM UTC.