I really enjoy puzzle games. Here’s a list of some I’ve enjoyed:

• 3D
  • Antichamber
  • FRACT OSC
  • Kairo
  • Portal (2)
  • The Talos Principle
•  Platforming
  • Braid
  • FEZ
  • The Swapper
• Pure
  • Hexcells (Plus / Infinite)
  • Picross 3D
  • Slitherlink
  • SpaceChem

All of these are well worth buying.