
This is especially useful in any challenge where Isaac is Blindfolded, as the second player will be allowed to fire tears normally. Challenges can be played in co-op, allowing a second player to contribute to the run without being hindered in the same way Isaac is.However, there are a few strategies that can apply to all challenges. Each challenge has certain strategies that can be employed to make the run easier. Some challenges do compensate for this by being especially punishing Solar System is a good example of this.

This doesn't mean all challenges are difficult, however challenges like Computer Savvy are quite easy to beat. Most challenges are designed to increase the difficulty of the game in a unique fashion. Players, with the advent of modding, have created their own Custom Challenges too.

Each challenge unlocks new content for the game, such as runes when completed. With few exceptions, Treasure Rooms are not available during challenges. Isaac typically starts each challenge with one or more specific items which makes normal play more difficult.
