Guest Post, Immune Defense Discussion

Elizabeth “Li” Van Nostrand writes about biology, psychology and video games at her blog, AcesoUnderGlass.com.  She is a rare sciencer/gamer person.  She was kind enough to give us some comments on her experience playing Immune Defense.  My replies are in grey.  You can see, she gave me some excellent questions.  I think this conversation here makes many aspects of our science game design clear.  

• The receptors are incredibly picky about where you have to place an attractor for it to pick it up.  This was fine when it was the challenge mechanic, but was really frustrating on higher levels that required more strategy.
• The attractors (purple boxes and ATP) fade out pretty quickly.  If the neutrophil is far enough away there is nothing to do but create a bread crumb trail.  This was kind of fun in the lower levels, but it is way too much to do (in part because see above) in the higher levels.   And at level 5, when you have a larger map but only one release point, it was incredibly frustrating.

You have picked up on something the best game designers are telling me, and that I feel myself as well: we can have strategy or tricky speed racing with cytokines, but not both in the same level.  The strategy part: which cell to use to kill which pathogen, whether that cell should be activated, what is the least inflammatory and cheapest way to clear the field–this part is what we want to focus on in levels 5 and 6.  We are working on an experimental set of levels that we think will draw out the strategy aspect.

• Difficulty moving also encouraged me to use a single neutrophil in an area and switch its target type back and forth, which felt wrong science-wise and was more micromanagement than I wanted game-wise.
•  My main strategy with macrophages was to let them wander off, but grab their signal molecules when I wanted to amplify a particular neutrophil.  As game play it was actually kind of fun, but I am pretty sure that is not how it actually works.

In real life, cell do change their surface molecules, and the sometimes change them very quickly.  However, they definitely do not change them back and forth over and over within minutes, like we are encouraging players to do in the game.  Additionally, Macrophages do send their signals out so that Neutrophils can receive the signal from a bit of distance.  In both of these cases–surface molecule switching and grabbing a signal molecule when you want to activate a specific Neutrophil–we let the player do because we want to show the player WHY a cell would want to change its surface molecules and also explain the RANDOM nature of signal diffusion.  We are trying to prime players for learning more: about gene regulation, that each protein serves a specific purpose, and therefore, why mutations make such problems.  Learning about organelles and proteins production is tedious, but if we already know why a cell changes it’s surface molecules, we are primed to start learning how it does.  

• The shift button doesn’t work very well for creating trails because I can only pick up as many attractors as fit in the cursor.  Maybe let the player keep pick up more molecules as they move the cursor?
• Overall the fact that I had to do so much work to create trails to get the neutrophils where I wanted kept it from feeling like a true tower defense game for me.  I wish it was a little more like majesty, where you just create the set up and then let them run.

I think you will enjoy our upcoming experimental levels. Your comments align with our own thoughts and we are working toward 1. Making molecule movement something that is fun to do, and not such a chore and 2. Making it easier to target cells to particular pathogens/making cells more dependable, while still preserving the reality of the random nature of cells finding their way.   We think that allowing the player to use precious energy to ensure a cell reaches a target quickly will be a nice balance.  we will keep working on our level design until the strategy is fun and manipulation is too cumbersome for each level.   

• If a macrophage gets on top of a bacteria (especially in a corner), it will eat all the signal molecules and there’s nothing to attract a neutrophil.  I can’t even grab molecules to make a trail without insane reflexes.  Even nearby, the neutrophils seemed incredibly bad at getting to pathogens on their own.

At this point, I always turn off the Macrophage’s receptors, and then it releases the bacteria.  This is unrealistic, but the issue does teach players a real aspect of signing: other cells with receptors for your signal affect the distribution of your signal.    

• Adding multiple new options in a single level made it hard to learn them.  But I know this is a demo and you only have so much space.
• Modern gaming has taught me not to read instructions, just start playing and figure it out/wait for in game guidance.  I barely skimmed the cut screens.

Yes, if we give the player fewer new tools in each level then there will also be fewer instructions required, and we should be able to design the levels so they can be figured out by poking around.  We have been moving in this direction for the past year and our test players have responded very well.  One year ago, level 1 was so complex that no one played level 2 voluntarily.  We have made it simpler.  However, no one wants a really simple “just click where ever the arrow points” experience, so we have to iterate and iterate to create a level that shows a lot of cool details and involves the player at just the right level of detail.  

• music volume controller would have been nice

Yes.  We need to balance the music and sounds and I would love a volume/mute.  

• But those were pretty minor, I had a ton of fun playing Majesty.  I also thought the science was well done and I feel like I have a deeper understanding of immunology than I did before.  The simplifications you made (like being able to swap receptors on an individual cell) felt like reasonable concessions to game play that didn’t lessen the educational aspect (exceptions listed above).  And I didn’t think about the graphics or controls (except for shift) the whole time I was playing, so they are doing their job.