In each level you are given one primary objective, and then you are given a list of optional missions in which you can take along side those. (darkstation.com)
There are optional missions for characters you meet throughout the game, and you can compete in the arena for money and better weapon unlocks. (apgnation.com)
The guide will be updated later with optional missions, bonus boxes and crossover coins. (disneyinfinitycodes.com)