A GM can change up a monster by altering its appearance, adding a simple template, or giving it class levels. Of these options, adding class levels is the most time-consuming for busy GMs, but it also results in a monster that is truly different. To simplify that process, a GM can apply a simple template that adds a class’s key features to a creature without drastically altering all of its statistics.
Simple class templates function in much the same way as all other simple templates. They enable GMs to customize creatures by giving them the flavor and abilities of classes without the complexity of adding class levels.
All simple class templates have two categories of changes.
The “quick rules” present a fast way to modify a creature’s abilities and statistics without having to actually rebuild the stat block. The “rebuild rules” list the exact changes to make to the base stat block if you have the time to completely rebuild it, such as between sessions when you are planning the next game. The two methods result in creatures of similar (if not identical) abilities. These templates grant their respective classes’ class features, which are denoted by a dagger (†). Many of these function slightly differently than the original class ability, as noted in the templates.
Spellcasting: A number of these templates grant the ability to cast spells as a member of the class on which the template is based. These templates only grant spells for the three highest spell levels the creature has access to. If the creature casts all of the spells of its higher levels, you can keep the combat challenging by adding lower-level spells—denoted by a double dagger (‡)—but no more than two for any given spell level.
Pathfinder Roleplaying Game Monster Codex © 2014, Paizo Inc.; Authors: Dennis Baker, Jesse Benner, Logan Bonner, Jason Bulmahn, Ross Byers, John Compton, Robert N. Emerson, Jonathan H. Keith, Dale C. McCoy, Jr., Mark Moreland, Tom Phillips, Stephen Radney-MacFarland, Sean K Reynolds, Thomas M. Reid, Patrick Renie, Mark Seifter, Tork Shaw, Neil Spicer, Owen K.C. Stephens, and Russ Taylor.