Copyedited by Cranberry
Thank you to garet_jaxx, reiksguardsknight and sirhatter. And very big thanks to kemwek for noticing in the early phase of the research that who clicks the go button first matters for displayed icon purposes. Thank you to Jason, who helped me a lot with the research. Thank you also to others who supported me so I was able to put an end to the mystery of displayed defence icons.

First, I want to state that you must completely ignore the defence icons (






) shown in the battledome unless you’re really knowledgeable about them (ie, for testing purposes). I will also refer to "defence icons" as "blocked icons" in this article. How those icons are displayed in the battledome will be explained in the second part of this article. Ok then, let’s get to the point.Defence weapons in the battledome fall under two major categories: percentage defence and non-percentage defence. (Weapons with special defence effects, such as Jhudoras Wand, won’t be discussed here.) Percentage defence consists of full blockers and partial blockers. The best-known full blocker is Thyoras Tear, which fully blocks all icons. Another example is Rod of Dark Nova, which fully blocks dark and fire icons. An example of a partial blocker is Downsize!, which blocks half of all icons. Percentage defence doesn’t depend on your defence stat.
Unlike percentage defence weapons, non-percentage defence weapons depend on your defence stat. They also depend on your stance, but are not affected at all by your opponent's stance. The damage you block is equal to the standard defence icons of the weapon * your stance multiplier * your defence boost. You cannot block more damage than you receive (in other words, you can’t get negative damage). And don’t forget, just ignore the displayed defence icons.
A quick summary:
Percentage defence weapons = Percentage defence * damage done by opponent (the corresponding icons only)
OR: Percentage defence * opponent's actual icon * opponent's strength boost multiplier * opponent's stance multiplier * your stance multiplier
Non percentage defence weapons = Standard defence icons * your stance multiplier * your defence boost multiplier
Note that you can't block more damage than you receive. If your opponent does 5 damage, and you're supposed to block 10 damage, you will still block just 5 damage.
Congratulations! You have finished the first step in understanding the defence system in the battledome. The next section contains the algorithm for how the defence icons are displayed and explains why they are so varied and so on. I'd advise you to proceed only if you’re already advanced in the battledome system, so if you’re not really that good, please stop here.
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This is the beginning of the second part of my article explaining the algorithm for displayed defence icons. Again, please don't mix up the defence system with the defence icon system. A quick summary: each defence icon shown in the battledome (for both sides) is determined by the strength boost multiplier of the person who clicks the go button first. For example, C has the 700 strength boost, and he defends and clicks first. Then each defence icon shown in this case is worth 15 damage (it blocks 15 damage). Please remember that "fractional" icons might appear. A full explanation is below.
A quick summary:
Blocked damage = actual shown defence icons * first person who clicks the go button's strength boost multiplier * your stance multiplier
Note that you can't block more damage than you receive. If your opponent does 5 damage, and you're supposed to block 10 damage, you still block just 5 damage. "Actual shown defence icons" means the icons displayed might be fractional icons that get rounded up for display purposes.
To help yourself understand the "currency conversion rule," imagine those strength boost multipliers as water and the defence boost multipliers as buckets – A's with a capacity of 1L and B's with a capacity of 0.5L. These capacities are referred to as "currency." If B clicks the go button first, A has to deal with B's currency, which means now A will be using two 0.5Ls of capacity instead of 1L of capacity. Again, please remember that this currency system only affects the defence icons shown, not the attack icons/actual damage.
In this example, B attacks with water, clicking the go button first, and A uses leaf shield. Since leaf shield's standard water defence is 5, A's water blocking capability is represented by 5 1L buckets. But since he has to deal with B's currency, each 1L bucket is replaced by two 0.5L buckets, for a total of 10 0.5L buckets – meaning there are 10 water defence icons shown in the battledome. This means that A could block up to 10 water icons from B's attack (or from anyone with the same strength as B ).
So, B attacks with 5 water icons (each worth 0.5 L). A still has 10 0.5L buckets, but only 5 buckets are filled with water (blocking B's attack), while the other 5 buckets are empty. In this case, since A blocks all B's water, B does zero damage to A.
Then let's say B attacks with 15 water icons. Now all 10 of A's buckets are filled with water, and A can't hold the other 5 waters from B. Therefore, B inflicts 5 water icons (2.5 water damage) to A.
What if A clicks the go button first now, still using the leaf shield? Since he'll be using his own 1L capacity as currency, A's water blocking capability is represented by five 1L buckets, meaning there are 5 water defence icons shown in the battledome. This means that A could block up to 5 water icons from B's attack (or, again, from anyone with the same strength boost as B).
So lets say B attacks with 5 water icons. Since B's water icons are only worth 0.5L each, the water attack will only fill 2.5 of A's 5 buckets. In other words, B does zero damage, same as before.
Then let's say B attacks with 15 water icons. Now all 5 of A's buckets are filled with water, and A can't hold the other 5 water icons from B. B inflicts 5 water icons (2.5 water damage) to A – again, same as before.
Let's switch. A attacks, and B defends, using leaf shield. Let's say A clicks the go button first. Again, leaf shield's standard water defence is 5, so therefore B's water blocking capability is represented by five 0.5L buckets. Since he has to deal with A's currency, each two 0.5L buckets become one 1L bucket, for a total of 2.5 1L buckets. Of course, literally speaking, there is no 0.5L (half-)bucket, so his remaining 0.5L bucket will be represented by a 1L bucket that can only be filled halfway. So B will have 3 (rounded up from 2.5) buckets instead, which means there will be 3 blocked water icons shown in the battledome. This means B could block up to 2.5 water icons from A's attack (or from anyone with the same strength boost as A).
So lets say A attacks with 2 water icons (each worth 1L). Those 2 water icons will fill 2 of B's 3 buckets. Thus A does zero damage to B.
Then let's say A does 3 water icons. Even though B has 3 buckets, one of the buckets can only be filled at most halfway -- it can only hold 2.5 water icons. The rest "spills over," meaning A does 0.5 water damage to B.
That's how the variable defence weapons get "modeled" into simple scenarios... but how about percentage defence weapons?
Let's use A and B again for the example. Let's say B clicks the go button first. A attacks B with 10 water damage (worth 1L each). B uses enchanted kiko squeeze toy, which can block 100% of water. Since B has to deal with his own currency (which is 0.5L), B will be using 20 0.5L buckets (that is, the number of blocked water icons shown in the battledome will be 20) to hold all A's water attack. And so on.
What's the conclusion? A person with a certain defence boost, using a certain defensive weapon, actually has the same damage-blocking capability against his opponent, regardless of the opponent's strength and the defence icons shown. The defence icons shown in the BD vary because they have to be adjusted for the strength (or "currency") of whoever clicks the go button first.
Percentage defence weapons' displayed blocked icons depend on the attacker's icons -- the more damage dealt by the attacker, the more blocked icons will be shown. The attacker's strength boost and the stance used are taken into consideration. By applying the conditions given above and the "currency conversion rule," we can conclude the formulas as follows:
Icons shown = Defence percentage * attacker's actual icons * attacker's strength boost multiplier * attacker's stance multiplier / first person to click the go button's strength boost multiplier
Note that fractional results will be rounded up in the battledome for display purposes.
This formula also works for reflectors -- just replace "defence percentage" with "reflection percentage."
Non-percentage-defence weapons fall into two categories: variable defence weapons (which display a varied range of defence icons), and non-variable-defence weapons (which display a fixed number of icons). An example of a variable defence weapon is Leaf Shield, and an example of a non-variable-defence weapon is Steam Jug.
So what are "variable defence weapons"? Variable defence weapons are weapons that have either a specific standard constant or ranged amount of defence (a constant, for example, would be 5 earth, while ranged would be 1-5 physical). They are not percentage defence; therefore, they don't depend on the opponent's attack. Variable defence weapons' blocked icons depend on the defender's defence boost and don't depend on stance at all. They also only display defence icons that are actually used against you -- for example, if your opponent uses a minimum of 1 water, your leaf shield will show water defence, but if your opponent doesn't use water at all, your leaf shield won't show any water defence. By applying the conditions given above and the "currency conversion rule," the formulas are concluded as follows:
Icons shown = Standard icons * defender's defence boost multiplier / first person to click the go button's strength boost multiplier
Note that fractional results will be rounded up in the battledome for display purposes.
Here, I'll give you a flash thingy you can use to practice and learn for yourself. A is the attacker and B is the defender. You can set who moves first, their stats, and their weapon's icons.
http://idb.finalhit.org/uploads/Phoenix/vardef.swf
http://idb.finalhit.org/uploads/Phoenix/def.swf
You have finished reading all the important things, but before I end this article, there's still one thing I want to say. Please note that this article won’t totally apply to "error" weapons that display blocked icons but don't actually block anything, or weapons that don't display blocked icons but do actually block something.
That's a great article, and I learned a lot while editing it!