Magic in HP is just not that well defined and there is a definate lack of spells to use. Many spells were cast nonverbally, but as there was no specific boundaries set on any of these spells, Potters Army has its own custom spells that you can use. Battles and duels are fairly common at PA, and therefore we created the Spell Compendium.
Basically, the spell compendium is a list of made up spells (mainly derived from latin) which allow you to do stuff that you couldn't with the known spells in the series. During duels, only the spells shown here can be used. This way, no one will be doing odd spells nonverbally and doing magic which is against their limitations.
The list is a joint list of canon (in case anyone needs to look them up) and invented spells. The spells are divided into several categories:
Charms- Charms are a type of magic spell concerned with enchanting an object to behave in a way that isn't normal for that object. Charms are usually defensive magic, and are quite different to curses, hexes and jinxes in that regard. However, charms can be used in an offensive way, such as stupefy.
Jinxes and Hexes - These are spells that cause minor harm to the victim.
Curses - Like hexes, but have a far more negative effect. Most dark magic spells are curses.
Transfiguration - No incantations. Transfiguration is the art of transforming an object into another shape or a different thing completely. You can also conjure and vanish objects in Transfiguration
Enchantments - Enchantments are long lasting spells used to defend or enhance an area.
There are also Magical Abilities like occlumency, leglimency, alchemy and many others. These are listed in the Magical Ablities thread as they do not belong at the Spell Compendium.
The spells are also divided by how advanced they are, and people on a lower tier level are not able to use advanced spells. For more information about that, see the Tier list. Also note that higher Tier characters can use NEWT spells far more effectively than NEWT students.
Other than that, some spells require specific abilities to be used. For example, Fiendfyre requires Dark Magic and Tier level of 3. So you would have to apply at the abilities and skill thread for dark magic before using that spell.
The Spell compendium also lists the boundaries of spells which are likely to be abused, and you don't want to be caught doing that.
The spell compendium is almost finished. It would be very helpful of you to point out any mistakes or add in any missing canon spells. Just PM me with the missing ones in the code. Also, member created spells will be listed at the spell compendium as well. Therefore, over time the PA spell compendium will grow even larger! The spell compendium was created by both Vincent and I. If you want to use this spell list on other sites, feel free to do so, but please list where you got it from