How Do You Approach Games You've Finished Again?

[Viiper]

Give yourself little mini-challenges.

In FF6 or Shining Force I only get the characters who are required.
For Pokemon Fire Red/Leaf Green, only get Pokemon that are given to you. You end up with a starter, Eevee, fossils, Hitmonchan/lee, and Lapras.

I like when games have these built into it. Like Halo has "skulls" which are kind of like optional challenges for going back into the story mode again. Bastion also had a system like this called "idols" which would provide ridiculous challenges.