if you don't mind I will post the answers

ok.

This game is perhaps the most unique entry in the GOG library
Witcher

Myst spinoff?
Uru

This Microsoft series is an icon in PC gaming but is sadly missing from GOG.
Age of Empires

Deus Ex 2.5?
Project Snowblind
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There is no game starting with this letter on GOG.
Q Y

I'm in a train!
Last Express

Don't let these cute little guys deceives you - they carry quite an impressive arsenal.
Worms

This giant is a citizen of the Island.
Kabuto
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Verne would probably not have been too pleased with this one.
Journey to center of the earth

Originally released in 1999, this critically acclaimed game saw a re-release in 2010 on Steam.
Alien vs Predator

Despite its steep learning curve, it has become the flagship series for its well-known European developers, who are known for this specific genre of game.
Europa Universalis

This game shares its starting letter with only one game on GOG. It is also considered one of the best games ever made.
X-com
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This adventure game series (one of which was remade VERY recently) is comprised of __ games.
Space Quest 6

Overthrow an evil dictator in this action game.
Just Cause

A truly 3D strategy game.
Homeworld

You play Ben in this classic adventure game, which includes many Star Wars references (for obvious reasons).
Full throtle