In this, the last prototyping session of the semester, the team continued work on the castle-building game that we had begun the week before. By the end of the previous meeting, we had made a good start and we had a fun game. This week was mainly refining, adding new features to make the game more interesting and polishing existing features.

The week before, we had necessarily focused mainly on playability and designing a prototype that would actually be a decent representation of the kind of gameplay we wanted, and we glossed over many of the finer details about the workings of medieval castles. While we incorporated concepts that we had come across in our research, like machicolation, we didn't put too much emphasis on making sure that the way we implemented them was completely historically accurate. So, one of our first tasks this week was to go back to our sources and try to adjust or add to the different elements we had included so that they better reflected the reality of medieval castle building. For example, we had previously made a rule that adding machicolation to the top of a tower extended the range of the archers on top of that tower. However, that was not actually an accurate representation of the effects of machicolation--what it actually does is allow archers to fire nearly straight down on attackers at the base of a tower without exposing themselves to enemy fire, an ability that normal crenellated towers did not afford. We had also fudged a bit in our calculations of damage that attackers could do to the castle--for example, we had included mechanics that permitted attackers to shoot down defenders who were inside towers, but in reality, this would have been impossible, since most towers were equipped with arrow slots that allowed defenders to fire out but stopped outsiders from firing in. This week, we went back to the books to cement our understanding of many of these elements and changed their implementation in the game so that they better reflected reality.

In addition to fixing these inaccuracies, we added or updated a number of elements that players could choose to build. For example, while machicolation was an extremely effective method of wall and tower defense, but sometimes resource availability, time, or knowledge might have prevented its construction. The latest versions of our prototype included other options for tower augmentation, like hoardings, which are a sort of wooden version of machicolation, or crenellations, which are simpler to build but provide slightly less flexibility and protection for defenders.

We also experimented with varying the resources available to the player. In the previous iteration of the prototype, the player had three in-game months to build up their fortress in each building phase, but this was the only limiting factor on what they could build. This week, players were required to keep track of how much lumber and stone they had available, as well. Adding this dimension to the game seemed to give the players more interesting decisions to make during the building phase and was overall successful. We also tried adding water as a resource for the creation of moats, but this didn't actually add anything to the game because no playtesters ever came close to running out of water when they started the round with a reasonable amount. We also tried having food as a resource, so that the player would have to build a fortress capable of repelling attackers before food stores ran out, but this added a dimension to the game that we didn't like--we felt that having to worry about food stores took the focus off the actual castle building.

Sadly, since this was our last week of prototyping, there are a lot of potential improvements and expansions that we didn't have a chance to add. Real-life castles were incredibly complex and although our prototype ended up fairly complicated (at least for a paper prototype), it only explored a tiny number of all the possibilities open to us. There are still a number of ideas we wanted to add but never got around to, like bartisans, turrets that projected from walls and allowed an occupant to rain death down upon enemies from all angles while remaining completely protected, or sally ports, heavily protected doors, just large enough for a mounted knight, that allowed defenders to send out sallies to destroy enemy siege weapons. Additions like sally ports would also give the player the opportunity to do something more in the attack phase. Instead of just passively waiting on the outcome of dice rolls, they would have the chance to decide whether to send out a force to attack a trebuchet and how many men to send. This could also add another angle to resource management, either in the form of a new "knight" resource or by requiring the player to decide how many defenders to take off the tower and hold in reserve at the sally ports.

Another idea we never really got to try involves incorporating the differences in castles in different regions and times. The first medieval fortifications in England and northwestern Europe were relatively simple wooden affairs, usually just a large keep on top of hill surrounded by a fence. As time passed, more innovations and improvements were made to the building process, until eventually castles became massive, near-impenetrable fortresses. For example, when people started making towers from stone, it became possible to build round towers instead of square towers, which were advantageous because they didn't have "dead angles" that couldn't be covered by defender fire and allowed enemy forces to attack the walls. It would have been fun to experiment with setting different rounds of the game in different periods and giving players different levels of technology to how it affected their playing and enjoyment of the game.

And, as always, there are still some issues and problems that we have to work out. The attacking army movement and rules for combat and damage still need some tweaking: obstacles, for example, do far more damage than they probably ought to; the trebuchet is probably more random than it ought to be. Towers also give us a little trouble: should players be able to repair recycle rubble from demolished towers in later rounds? What about the scenario where a player puts hoardings on top of a tower, but then later decides they want to build the tower taller? These are issues it would be interesting to address through further playtesting and revision.

Still, we ended our semester with a game that, while far from perfect, is a lot of fun. Players seemed to enjoy not just the opportunity to juggle resources and play with different castle set-ups, they also got found themselves on the edge of their seats during the attack phases, waiting to see if their constructions would hold. Even the GMs who rolled the dice and calculated the damage done each turn became surprisingly invested in the attack phases and the fates of the two sides, given that they had no decisions to make and no input into how the round played out. One amusing development was the way that the attack phase often seemed to play out as a story, players and GMs exclaiming or groaning as parts of attacking armies accidentally impaled themselves on obstacles or when the trebuchet destroyed a tower. The last playtest worked particularly well in this regard, ending in a nail-biter in which a huge invading army was reduced to its last handful of fighters facing off against a single remaining tower of defenders. It looked like a certain victory for the defenders, protected behind their stone walls, but a lucky hit from the trebuchet at the last possible second brought down the tower and the defenders inside. The attackers "won", since they had destroyed the defending army, but in the end there was only one attacker left. Even a couple weeks after that playtest and the end of our work on the castle-building prototype, we still laugh at the image of that single, solitary viking sitting alone in the keep, maybe hanging out with the cows or other farm animals that were the sole survivors in the castle.