Increased electric field

Increased magnetic field

Increased magnetic field and electric field

Increased charge of the particle

Increased charge of the particle and magnetic field

Cooling the magnet

Striking the magnet with a hammer

Dropping the magnet on the floor

Heating the magnet

All of these will cause a magnet to lose strength

Cooling a permanent magnet

Heating a permanent magnet

Adding an external magnetic field to a diamagnet

All of these scenarios lower the effective magnetic field.

Dropping a permanent magnet on the floor