Blog necromancy! This entry is a few years old (cross-posted here from an older blog), but remains valid in terms of design philosophy.
In game design, “too powerful” is a misleading phrase. The actual design should reflect “It needs to cost more.” A power or effect should remain pretty true to its original design. Mind control needs to feel like mind control — you can’t take a little bit away from it and hope to elicit the same in-game effect or the same player enthusiasm. A lightning blast needs to be a levinbolt that electrocutes its target, not a wee spark that sizzles foes for a li’l bit of damage. Hyper-speed needs to be fast… no, faster than that. David Bowie’s cone of frost breath weapon needs to crystallize targets caught in the blast radius.
This isn’t to say that there’s no place for low-powered effects. Those certainly have their place, particularly in level-based systems* that gradually step up the potency of what players can do. In these cases, the price is still important, and they still need to be relative to the effect, so it stands to reason that the costs should be commensurately lower.
One of the design philosophies that resonates with me is that all special effects should feel overpowered. As the player, I’m the coolest thing in the game, so everything taking place in the game should reward me for being there. When I do something — particularly something that my character has as an edge, such as a superpower, special skill, or supernatural ability — I should say “WOW!” when I use it. This engages me and empowers me. This is one of my rewards for spending time with the game. This can be a visual effect in a video game, a chance to spend a unique resource in a board game, an effect only my character type can create in a tabletop RPG, or the ability to use a special type of card in a card game.
My choice in choosing a play style contributes a lot to this. If I’m a psychic spy, my WOW! moment might be using my psychic powers to command or confuse my enemies. If I’m a wizard, it could be an icy blast that freezes my enemies, causing them damage and immobilizing them. A fighter type can stun an opponent with a rabbit punch or disembowel him with a dagger.
The fact that it feels overpowered doesn’t mean it should be overpowered, though, and that’s where the cost to create effects comes in. A particle effect and some audio feedback in a video game can provide that overpowered-feeling WOW! for even an average effect. Rockets and missiles in EVE, for example, land with a resounding explosion that feels very satisfying. They don’t do inordinate amounts of damage, but they feel exciting when they hit. Every character class in D&D 4e has nifty “at-will” powers that feel unique and exciting, even though they really amount to little more than a basic attack with a minor bell or whistle attached. The Disciplines in Vampire make the Kindred a cut above mortals, and since there are way more mortals in the world than there are vampires, Disciplines are both rare and empowering. The prices to invoke all of these effects, whether it’s ISK-per-missile, blood points, or frequency, keeps everyone important — players — on the same playing field.
That’s the challenge — creating the feeling of awesome while still preserving the integrity of play through managing the cost of effects in resources.
* (Now, one of the perils of level-based systems is that the mathematical challenge increases in sync with the ability of the character, so that things often don’t really become more difficult, the numbers behind them simply become greater. In many of these cases, the character’s frequency of success remains about the same — he’s trying to reach a higher threshold, but his bonus modifiers to get there are higher.)