One final thing to keep in mind when evaluating the combat of a video game is the risk-reward of player actions. Though the gameplay mechanics and core dynamics may govern which actions are counters, the gamestate gives context to those actions. The same move can be overpowered in one situation or pathetically useless in another. Some games are designed with specific features to significantly affect the risk-reward balance or context of actions based on how much a player is winning or losing. There's a good reason why a design would want to do this. But first, we need definitions.
Piggybacking off of this excellent article by David Sirlin, I present the following terms.
Watch your step Sonic! It's a slippery slope.
Consider two main ways to create slippery slope gameplay. When a player falls into a disadvantaged situation, if the player loses mechanics, viable options, or resources they'll be doubly disadvantaged. With less to work with, the double disadvantaged player will be less capable of preventing the next attack thus slipping further behind. In other words, games that feature decay dynamics can easily facilitate slippery slopes. Such games include Chess, StarCraft, and Advance Wars.
Sirlin gives examples of "limited slippery slope" that start and end so quickly, they don't have a chance to snow ball into significant disadvantages. I prefer that we don't use the term slippery slope for examples so minute. Like elegant solutions and nuanced mechanics, we must use judgement to determine slippery slopes even if doing so introduces some subjectivity to the discussion. Otherwise, almost any disadvantage can be viewed as a slippery slope.
Because the slippery slope merely refers to the relative widening of the gap between players, the other way to create a slippery slope is to give a player additional advantages for earning a slight advantage. In other words, instead of the other player getting weaker and less capable of fighting back, the disadvantaged player's abilities stay the same while the advantaged player gets stronger. "The rich get richer." Examples include EX meters in Street Fighter 4, powerups in Bomberman, grabbing coins and item boxes in Mario Kart, and the COD:Blops game type Gun Game.
When a game has too steep of a slippery slope, small leads at the beginning of match can easily snowball into a large game winning lead. Often times, competitors don't even play these games to the end. With a hand shake, a toppled king, or a "gg," losers of a match recognize when they're beat long before they lose by the game rules. (perfect example here. StarCraft 2 match with commentary) So you have to ask yourself, why bother designing/playing a long game when the victor is decided early on? How significant are a losing player's actions and choices if there's really no chance of coming back and winning?
Mario's got an Ace up his sleeve! I smell a comeback!
To keep things interesting from start to finish (ie. all players can win), designers can employ comeback mechanics/features. These elements of design give losing players certain advantages to even things out, but this doesn't mean they're guaranteed to rocket back into first place. In all the games I've played, comeback advantages can be squandered, misused, or countered just like any move. If successful, comeback mechanics are generally designed to greatly reduce the gap between players.
It's important to understand slippery slope and comeback design because of how they affect viable strategies and options. Try watching a sports game with the score covered up or a fighting game match with the health bars concealed. Without this information, it becomes much harder to understand why players make certain decisions or what's going through their minds. Without this information, we can easily become disengaged with the active combat. If you can't accurately judge the risk-reward of actions, then you're missing the point.
The following are examples of comeback mechanics...
Give and You Shall Receive. The same attacks that you use on the opponent can be used directly as fuel for a counter attack.
What Doesn't Kill You Only Makes You Stronger. Taking damage, hits, or other kinds of disadvantages indirectly feeds a comeback mechanic (generally through some kind of abstract dynamic/meter).
Table Turners. When your particular disadvantaged state is swapped with the opponent's advantaged state.
Ace Up the Sleeve. You have access to these powerful/comeback mechanics at any time. Their use is generally limited because they're difficult to pull off.
In part 6 we'll look at where slippery slope and comeback mechanics meet free-for-alls.