Special actions are unique abilities that can be used by hitting the action button. They are either used for utility functions, like teleporting or pickpocketing, or offense, like fire breath.
Their effectiveness is based on a corresponding stat (Pickpocketing is based on Dexterity, etc). The higher your corresponding attribute is, the more effective the special action usually is in some way - attacks have more dice of damage, there is an increased chance of an ability working, or duration is extended, depending upon the ability in question. Some special actions (such as Dimensional Move) do not have any scaling effects, however, and do not change regardless of your stats.
Special actions use up Stamina; attempting to use a special action while affected by the Tired condition may result in failure to utilize the action (Stamina cost is still applied if failure occurs); attempting to use special actions while affected by the Very Tired condition or worse will always result in failure. It is possible to reduce yourself to the Very Tired! condition by repeatedly trying to use special actions, so be careful.
Using special actions trains the attribute it corresponds to. This means that special actions that are self-targeting or otherwise capable of being used in general circumstances can be used in safe places to train your stats, as they only cost stamina, which you can rest to regain for as long as you have enough food.
Special actions can be opened up for use through the gaining of certain feats, belonging to a certain race (most are debug races), or reaching a certain level of a Skill. Special Actions may also be gained from being aligned with certain gods, and changing your allegiance would remove the skill.
Look at all of an adjacent neutral or enemy creature's items, apply sense quality to them if possible, and potentially choose one to try to steal (max weight str/2). Uses stamina regardless of whether you pick an item to try to steal or if you just take a look.
Draw charges from chargeable items, destroying them in the process. Number of actual charges drawn from the item appears to depend on the value of the item (number of charges drawn is always equal to or more than the number of charges in the item). Using this action on an item with zero charges will draw no charge at all, but still destroys the item in the process.
Fill a chargeable item with drawn charges. You need 10 drawn charges for one attempt at charging an item. The effect is similar to reading a scroll of recharge. Has a chance to destroy the item, which goes down with increased Magic Device.
Deals Nether damage to the enemy, thus stealing HP, like vampire bats. Based on Dexterity. Also restores some stamina, allowing you to use it to effectively gain back all your stamina on multiple or one tough opponent. Can be used with impunity on freely attackable NPCs in towns (or during Party Time! quests on weaker, unsupportive NPCs) to great effect, especially for spam-training non-combat skills.
Breaths fire, much like fire hounds and fire dragons. If you target the ground and use this action, it will breath fire in the direction of the tile targeted. Good for Russian-Roulette styled cooking. Based on Constitution.
Works like the Short Teleport spell. Has a 100% chance so long as you have stamina. Like short teleport, your destination is random and uncontrolled. Unlike the spell, it can be used safely while dimmed.
Cheer (28 SP)
Grants your allies the Hero, Speed, and Contingency effects for some time. Based on Charisma.
Breaths breath with the respective damage type out over an area. Comes in all the special damage types except magic; Power Breath deals normal, physical damage. When this action is used, the breath will be directed at whichever monster/NPC you are targeting at that moment; or if you're targeting the ground, in the direction of the area targeted. Based on Constitution.
Causes some damage and may weaken the enemy, reducing their stats until restored. Note that if your stats were enhanced by blessed potion of restore spirit/body and then weakened, neither drinking regular restore potion nor Healer's restoration can heal your stats. You have to drink BLESSED restore potion in this case. Based on Will.