You may want to start this series with part one, two or three.
Quest content design is hard: which is why so many quests are either Bounties or Fed-Ex quests. In their simplest form, a Bounty is a 'go get me x of y', and a Fed-Ex is 'take a to b'. But even these simple forms raise many interesting questions and hidden assumptions - and are worth examining further.
Bounty quests traditionally involve killing n rats where n > 0, but can equally be seen as collecting n items, for similarly sized n. But rats are traditionally difficult foes in quest design, because they make the following assumptions:
i. n rats exist to be killed
ii. the rats to be killed move slower than the player and remain in accessible locations which are known to the player
iii. the player always has access to the appropriate rat-killing equipment
iv. rats in the boundaries of the agreed quest location are only killable by the player, never by anything else including natural causes, or are else recreated through spontaneous generation if they are killed by other means despite the absence of a procreative rat population due to the ongoing rat holocaust
v. by rats, the quest giver and player automatically agree that this includes or excludes rats of a particular age, gender or profession, completely distinguishable and agreed postmortem, and that the moment of gestation of a rat is definitively known
vi. the quest giver has the omniscience to know when the player has killed n rats, or the rat evidentiary material required by the quest giver only ever exists on a rat in a singular form and cannot be subdivided and is only produced due to the specific actions of the player, or there is a thriving black market in rat body parts to the exact value of the quest reward
vii. if rat evidentiary material is required, this material is perfectly preserved in perpetuity and contained within an immaculate boundary which extends beyond the player's body sufficiently to interact with this material in a defined way, or if it should decay or be lost, the rat population should replenish itself miraculously
viii. the killing of rat n, is more interesting and challenge an exercise to the player as rat n-1, which was as fulfilling as rat n-2, and so on
Assumption viii strongly suggests that there should be an increasing challenge as the player progresses through the quest. One approach may be to simply have the initial encounter be with 1 rat, the next with 2, then 3, and so on, which will guarantee that nth rat will be as interested, provide n is on the Fibonacci sequence, or the remainder included in the final encounter. Another approach may be to scale the difficulty of locating or fighting each rat higher than previously, which could be achieved by placing them randomly across a location of varying difficulty (the player will naturally migrate to the easier rats first).
As you can see, the amount of effort required to ensure that Bounty Quests cannot be failed can be considerable, and are often diametrically opposed to suspension of disbelief. If we simplify a Bounty Quest so that we just count the number of times we perform an action, instead of counting the successful outcomes of an action, we end up with a Do Something quest. The Do Something quest is an instruction to do an action so many times: such as chin up exercises in Metal Gear Solid 2, or the fight tutorials in Zelda: the Wind Waker. The Do Something quest is far easier to measure, but does not necessarily gauge skill, just determination.
If you are interested in measuring skill, you could get the same effect as a Bounty Quest but with easier to control the outcomes by using an Arena, where we place the player in a defined area, and measure their actions. Similarly, puzzles, skirmishes and mini-games can be used to measure player mastery of a set of skills without the complex boundary conditions that a Bounty Quest demands. The benefit of the Bounty Quest is that we allow the player to suspend the quest while having achieved partial completion, and potentially replenish the resources they require from elsewhere in the game world. I would argue that this benefit comes at considerable complexity and inflexibility.
Fed Ex Quests
Let's look at the set of assumptions required to perform the minimal Fed Ex quest for which the game designer has made it absolutely trivial for the player to complete:
1. The item is provided by the quest giver
2. The player can carry the item easily and safely without impact their existing abilities
3. The player cannot drop, lose, consume, sell or destroy the item in question
4. The item has no utility value to the player
5. The player cannot find the item elsewhere
6. The player can reach the requested destination
7. The destination is at a fixed point in space
8. The destination is known in advance
9. There is no time limit
10. The shortest path to the destination is clearly indicated at all times
11. The shortest path to the destination requires no expendable resources be consumed
12. When the player reaches the destination, they automatically complete the quest
13. There are no other quests which it would be useful to be closer to the destination than the start of this quest
14. The reward for completing the quest is greater than any other bonus that the player could acquire with the same time and effort elsewhere
15. The completing the quest does not change the accessibility of any other game content
Some of these assumptions are involve complex logic, such as 1, 3, 4, 5, 6 and 12, where the wrong design can result in the player not being able to complete the quest at all. For instance, if the game designer has chosen to make quest items act like other objects in the game, which results in them sharing common code (command interaction, menus, physics engines and so on), the presence and reach-ability of quest items must be guaranteed at all times.
Taking a simple example of being able to drop an quest item from the player inventory. In this instance, the player must:
a. Be able to pick the item up again
b. Not be able to drop the item in an inaccessible area
c. Not be able to prevent themselves from reaching the area they dropped the item again
d. Any other actor which picks up the item must not be able to make it inaccessible
e. Any other interaction in the game must not be able to destroy or move the item so it becomes inaccessible
f. If the location containing the item is freed from memory, it must first be saved to non-volitile in a form which it can be retrieved in subsequently
g. Data structures and code must be bug free so that the item cannot be duplicated or lost
And so on. Note that some of the above assumptions may not be achievable at all within a reasonable development time frame.
Given the complexities of assumptions which can result in a game state where a player cannot complete a quest, it is amazing the lack of effort spent on varying the assumptions for which the failure states are far simpler to control, or impossible to achieve at all. Consider assumption 2. What if there were multiple parts to quest item, of which the player could only carry some of at one time. There is the classic puzzle example of crossing a river with a fox, a hen and grain, of which only two fit in the boat at any one time, and where the the fox cannot be left with the hen on either bank, and the hen cannot be left with the grain. These sorts of simple logic problems can be woven into a quest fabric where failure states can be controlled in a much more straight forward way.
Another approach to assumption 2 would be to turn the quest into an optimisation problem. Consider an example where the whole quest item consumes multiple valuable inventory slots, but parts of the quest item can be carried in single slots. The choice is then: do I give up equipment already in these slots (which presumably gives me greater capability to reach the quest destination), or do I make multiple trips, and so take longer to complete the quest? In these types of optimisation problems, there is no failure state, only a clearly delineated series of trade offs that the player must make. Assumptions 13 and 14 similarly encourage the player to think in terms of optimal route selection.
Take care when designing these problems that the process of solving it is interesting for the player. Inventory optimisation is already an interesting decision in Angband, so the inventory slot example is appropriate for that game, but in a game where the player never reaches their inventory capacity, this mechanic would be a waste of effort .
Let's turn the notion of Fed-Ex quest on it's head for a moment. If we start by violating assumption 14, and then progressively replace unique quest items with commodities through out the other assumptions, one natural conclusion is that the counterpart to the Fed-Ex quest is a trading game, such as Elite. In this genre, fungible, easily replaced items can be purchased and sold in multiple locations, and the player focuses on the strategy of buying low and selling high. It is possible to simulate this trading game using multiple Fed Ex quests to send the player along the optimal path, but this makes the assumption there is an easily discoverable path - which may not be the case in a game which simulates market conditions by varying prices over time. You may argue that the code complexity for an interesting trading game is high, but it is no more complex than some of the challenges I highlighted in simply allowing the player to drop quest objects. The fact that Fed Ex quests are more prevalent than trading games is because most games featuring Fed Ex quests don't allow you the luxury of dropping quest items.
If no tangible item is involved in a Fed Ex quest - e.g. no item that has any impact on game play other than a UI representation, we ensure that the quest meets assumptions 1 to 5 by default, and greatly simplify the implementation of the quest code. These simpler quests usually have the option not to deliver the quest item, so that the item has nominal meaning: this is usually a narrative fig leaf covering the fact that the player is simply going to a particular destination for the quest, where not delivering the item is the equivalent of 'I don't want to advance the story yet'. In any event, whether a player is given the choice or delivering the item or not, the result of this simpler Fed Ex quest is the Go To quest, where the player is told to go to a location, and does so. Assumptions 6 -15 then fall into two categories: violating assumptions 6 - 14 are ways of keeping the journey phase of the Go To quest interesting, violating assumption 15 is a way of keeping the consequences of the Go To quest interesting. The Go To quest can be seen as the atomic counter-part to the Do Something quest I discussed above. All quests consist of these two actions (Go To and Do Something).
Keeping the journey interesting is a function of ensuring the moment to moment game play is interesting - important in a game even without quests - while keeping the consequences of completing a quest interesting is traditionally seen as a much a function of narrative as it is of game play. It is consequences I want to talk about in the next part of this series, of success, of choice and of failure.
Saturday, 31 October 2009
You may want to start this series with part one, two or three.