20th Oct, 2013By Softmints2 minutes

This article is about ability resources: a type of mechanic which a moba designer can use to direct when a player should use their hero's abilities.

If an ability is free, a player will use it in every situation where it is beneficial (or at least, more beneficial than attacking, which is also free). It is usually more elegant to make this kind of ability passive or toggled.

Active abilities on the other hand should have some kind of cost. Cooldowns create what's called an opportunity cost: the cost of using an ability now is that it can't be used later. Cooldowns are widespread and with good reason; they introduce a choice element to ability usage.

Another kind of cost is the spending of a limited resource, which I call an ability resource. The most common ability resource is mana, which the genre inherited from Warcraft.

Mana has a couple of problems:

  • Downtime: Being out of mana is very crippling, and lasts for a long time due to its slow regeneration.
  • Restricts designs: Mana follows the attack pattern of a burst damage hero. It's difficult for mana to make sense on a hero which is intended to gain power as a fight progresses.
  • Numerical distortion: Resource management becomes less important as the game progresses, as mana pools rise while mana costs are static.

There are however, some advantages to mana when we're using it as a universal mechanic:

  • Greater variety of abilities: Examples include stealing mana from enemy players, dealing damage based on missing mana (a trump card for late in a teamfight), or absorbing incoming damage using mana.
  • Promotes teamwork: Players can help each other with their resource management by giving each other mana.
  • Coping strategies: Heroes have a wider variety of options for improving their ability resource management, because the same items work for every hero. In DotA, players can pick up Soul Ring (sacrifice life for mana), Magic Stick (generates mana as enemies use abilities), or many more.

A Dota2 hero gets their mana burnedMana as a universal mechanic adds a great deal of depth to the game, but its problems are also serious. In particular, one of the sentiments echoed by League of Legend's “design anti-patterns” is that mana burn, an effect which depletes an enemy's mana, is unsatisfying to play against because of the out-of-mana problem.

League has experimented with alternatives to mana for specific champions where mana just wasn't the right resource for those champ designs. However, these new resources like Energy and Fury don't interact with or benefit from the significant portion of items intended for heroes with mana.

Dawngate adopted the approach of making all ability resources shaper-specific and private. Many shapers don't have an ability resource, and just use cooldowns. The resources which do exist can't be meddled with by items or other players; they solely exist so the designer can influence when abilities get used.

This affords a great deal of control, but I feel the loss of depth isn't a good exchange.

A continuation of this article will be published at a later date.