Have some 90’s boomer shooters, roughly in the order they were released:
- Wolfenstein 3D
- Doom
- Doom 2
- Duke Nukem 3D
- Quake
- Descent
- Descent 2
- Blood
- Unreal
- Half-Life
- System Shock 2
- Deus Ex *
And some 2D point and click games:
- The Secret of Monkey Island
- Monkey Island 2: LeChuck’s Revenge
- Sam & Max Hit the Road
- Full Throttle
- The Dig
And some later games, that may or may not work without internet (*cough* Steam *cough*):
- Half-Life 2
- Deus Ex: Human Revolution
- Portal 2 (I’d include Portal too, but you said no entire series)
*) close enough to the 90’s