Difficulty in games we previously defined as variable sliders or smarter AI. In summary, to make the game more of a challenge either provide the computer player with more resources (variable sliders) or use the resources more effectively (smarter AI).
However, I want to introduce the idea of “complexity” in the context of game challenge.
Complexity is the number of mechanics, or underlying numbers needed to understand the game. In simple terms, complex games are hard to learn. For example Dwarf Fortress, most Paradox games, Warhammer 40k are all complex games because they have so many moving interconnected parts. Grand Strategy games, or simulation games like the Sims are usually very complex. Non complex games are like Tetris, or checkers, or some classic board games like Scrabble or Monopoly. Simple games usually only have a few affordances or mechanics that the player can do. In Tetris, the blocks fall and you move and rotate them. That’s it. The challenge of the game comes from “hp sliders” like speed of the blocks or type of blocks that fall. But every block follows the same rules. In checkers every piece moves in the same way (except the king pieces after getting to the other end of the board). Chess on the other hand, a more complex board game, has several different pieces each with their own set of movement rules. In complex games the challenge comes primarily from trying to understand what is going on.
So, what does adding complexity do to the game experience? Specifically, does complexity help us answer our guiding question of “How can we make a game more challenging?”
Think of complexity like a set of tools. Complex games have lots of specific, sophisticated and maybe dangerous tools. While new players are intimidated by the tool set and don’t know what to do with it all, experienced players can take the tools and build a “better” game experience (In this case better means easier wins for the player). So complexity does impact the challenge of the game. But it’s a different impact depending on how experienced the player is. More complexity for an experienced player will make the game easier because they have more tools to use. While less complexity will make a game easier for new players.
So, complexity and difficulty both affect the challenge of a game. Now, I haven’t introduced the term challenge, but it’s hard to define the difference between challenge and difficulty without an understanding of complexity. Challenge is the overall effort needed to win a game, including complexity and difficulty.
A few examples, let’s consider chess. To make a game less complex we remove some mechanics or underlying statistics of the game.To make chess less complex let's replace the knight with another castle. The knight piece is the only piece that can hop over other pieces, and it moves in a unique L shape. This makes it a relatively complex piece, compared to the castle which only moves in straight lines and can’t hop. Removing the knight completely also removes the mechanic of hopping pieces because no other piece has that ability. What does this change do to the challenge of the game? Well, for more experienced players you’re removing a key offensive piece. A lot of strategies are now completely invalid without the knight, and while I’m not a chess expert myself, for the sake of example I’ll just claim that removing the piece from the game would make it relatively more difficult for a player that’s used to playing with the knight. But for in-experienced players they no longer have to worry about a piece jumping over their carefully set up defences.
Let’s go back to our question of “How can we make a game more challenging?”. Now we have a few tools to answer this
The strategy you should use for your game depends on the game and is entirely up to the designer to figure out what strategy is best.