Here is an exploit using the game's text display speed. By setting the text speed to slow, you can have Oliver cast an innocuous spell like "Seek Fortune" (on the overworld) or any of the interior spells ("Levitate", "Chart Chests", etc.) and while the text message is being typed in the message box, enemies will be frozen in place. This allows Oliver to catch (or avoid) enemies easily, since you can move Oliver while the text is being printed.

Note that the "Veil" spell (from Horace's Riddles sidequest) will allow you to sneak up on enemies with 100% success ... but only if you've purchased the "Jack in the Box" merit award .