Ability

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An ability is a power which an entity possess which makes it more useful than something which attacks or defends, or in the case of effects something which just takes up an effect slot. Locations other than Plains can also be considered to have abilities, although they'll always be passive.

Activatible Abilities

Most of the time "ability" refers to a activatible power, denoted by "". These usually have a cost such as the user dizzying (), health (N Health:) or some amount of mana. Examples of activatable abilities include dealing damage to enemies (sniping), healing others, dizzying, and undizzying. Many activatable abilities can be viewed as stronger or weaker versions of various spells.

The Speed System governs in what order abilities take effect.

Passive Abilities

Not all abilities require activation. "Passive Abilities" can be divided into three types.
1: Abilities which list a time and happen every time that passes. An example is "End Turn: Red Goop returns to your hand.". Mana generation is a more common example of this: Generators could all say "Draw Phase: Gain (mana type)".
2: Abilities which are dependant on a certain event. "Enters Combat", "When Attacking" and "Into Play" are examples of this. A specific example of this sort of power can be seen on Valian Iridith: "When Valian attacks, you discard a card and gain ".
3: Abilities which are constant. Examples include D Damage: 50%, Entrenching, and Ability Shield. Another example of this can be found on Rainfields: "Cannot Cast Spells".

Failure

In addition, abilities are also susceptible to failure in the same ways spells are.

For activated abilities, countering it with a counterspell, not being able to pay its cost, or not having a valid target when resolving can all cause an ability to fail. Note: If the ability does not meet the requirements (i.e. trying to use TCPD's ability on an undamaged monster), the ability is not activated at all.

As with spells, the cost of the ability is everything before the colon (if there is one), the mana cost and the dizzy symbol (if it requires it to dizzy). Some entities which do not normally dizzy have a failure cost of dizzying, so that one will not be able to reuse the ability after being countered.

For abilities that target multiple entities (including passive abilities), as long as one of them is affected by the ability, the ability does not fail. However, if there is no susceptible target, the ability fails. If there is any additional effect, it will not occur.

Example:

Player A has a Cody (War) on the field.

When Player A uses Cody's ability, it first checks for its requirements, that Player A controls three heroes and at least one of them is undizzy. If there are not enough heroes or no undizzy heroes, then the ability is not even activated. If all requirements are met, it proceeds to pay the cost, which in this case is to dizzy all the heroes. If it cannot do so for any of the valid targets, if Player A controls a Ribbon for instance, then the ability fails and none of the effects of the ability take place. However as long as there is at least one target which can be affected, the ability does not fail, even if nothing has happened, i.e. an undizzy Shadehawk (VCH-Focus) with 2 other dizziable heroes.