I usually use Svetlana in the Time for Booze continuous event out at the north-east corner of the resort, over-the-water bungalows. These combined with a convenient source of sought item (read: duplication) makes for fast XP. Continuous events means those neverending side-quests where you can interact with the quest-giver to give them a constituent part or stackable that they seek, and they reward you with a different item, XP, and/or cash.Higher level enemies means more XP from their defeat. They will not be higher level than you if you have the enemy-level-adjustment option turned on. If you're playing in someone else's game and the host is a higher level than you or has progressed further, there'll be enemies that are higher level than you.IMMEDIATELY turn off the game without getting a check-point. switch to a character you want to give the XP to. Get a challenge up to where its about to finished. Anonymous claims that challenges can be exploited to earn XP from completing the same challenge over and over.As spartacus commented and kotekzot answered, your save file can be.
DEAD ISLAND SAVE EDITOR PATCH
This may still be viable if you are not on the latest patch (1.3). To get it out of the way, repeatedly breaking the same zombie's arm(s) was patched out, according to TheVoid (SDA).I'm assuming that these options may be faster than simply playing through the game. There are several ways: alter game files, redo challenges, play in someone else's game, repeatedly turn in continuous events, and/or repeatedly break zombie arms.