If you were wondering why Staff of Karnath replaced Sabre Wulf in this compilation, it's primarily due to the C64 version of Sabre Wulf being released a year after the Spectrum version.  Zzap! 64 reviewed Sabre Wulf in their November 1985 issue - which was the same month They Sold a Million was released on.
As for the compilation itself, Beach Head stands out head and shoulders above the rest, with Daley Thompson's Decathlon being okay (and having an early Martin Galway tune - his cover of YMO's Rydeen - during loading.)  Staff of Karnath was too frustrating, and Jet Set Willy is not a patch on its Spectrum counterpart.  The C64 conversion was done by Shahid Ahmad (Chimera) and he has detailed a lengthy insight into the making of before now which really shows just how much of a time limit he had to convert it.

Loved Beach Head as a kid, but never managed to take out the fortress. That gun coming to bear always freaked me out and threw off my ability to aim well.

I had this one for the zx spectrum, great collection.

This was one of my first purchases for the C64, it's good value for those four games at the time. I personally am not a Sabre Wulf fan, so it doesn't matter to me that it wasn't included (I am looking forward to the Sabre Wulf Remastered edition that is in development).

Staff of Karnath is a very atmospheric game. I love the loading tune and screen, and while the graphics are chunky (using the built-in sprite expansion), there are some great characters in there. Entombed is the best of the four Sir Arthur Pendragon games for me, but I have fond memories of playing this.

Daley Thompson's Decathlon is alright, ultimately I preferred Hyper Sports on the C64 and the Epyx Games series because they didn't just rely on waggling. The Daley sprite looks very odd nowadays!

I enjoyed Jet Set Willy at the time, but I can see the flaws now, especially the "endless death" syndrome where you repeatedly die. The Banyan Tree is notoriously difficult; I have only made it past there a few times myself.

Beach-Head is a classic. I love the various levels, but I always felt the tank section was the best part and wished there was more of it. The first time I made it through the hidden passage, I cheered. And I eventually managed to complete it.

I had never noticed the way the packaging has that advert-style page; it really is a waste of space!

I was hopeless at Staff of Karnath and the others in the series, but I thought they were incredible games. The feeling of open adventuring coupled with those big, varied graphics, I thought they were magical.

Never had that compilation of
THEY SOLD A MILLION,
but i still have the other pack -
with these classic games...

- BRUCE LEE
- MATCH DAY
- ENTOMBED
- MATCH POINT

...on the tape (boxed) for the Commodore 64 😺👍🕹️.

Somehow, i couldn't get ENTOMBED working 😿, but BRUCE LEE is the main reason for having that compilation 😺👍🕹️.

I''m sure there was a c64 version of sabre wolf but for some odd reason it wasn't in the c64 version.

They probably sold a million pennys worth, but certainly not a million pounds.
JSW looks like a speccy port running on the C64 speccy emulator, like the Dizzy Games, and seems the weakest. Daily Thompson was a poor mans track and field.  Staff of Karnath looks good but I never played it. Beach Head was on seemingly every compilation at that time.  Ocean had some great games on offer, but why they had to go with these games is a mystery.

C64 version of Jet set willy looks really poor version compared to the Speccy and Amstrad versions. Beach head wins though.

poor value for money,  don't like the packaging either