Mini investigation in using a shield

Background
A friend was seeking a shield for adventuring and as I looked through the armory testing different shield’s worthiness, I noticed that both a heater shield of fortification and one of invulnerability both provided the same AR. I decided to purchase a heater shield from a blacksmith in Britain (NPC) and found it provided close to the same protection. I pondered this anomaly for a bit and decided to launch an investigation. Was this a bug with shields? How many players actually use shields anyways and might notice such a glitch?

Investigation
Various heater shields were acquired and tested by a character with no Parry and one with GM Parry.

Results



Conclusion
Shields provide great bonuses to those with the Parry skill and are not worth equipping otherwise.

Discussion
While the results may be a “well duh” to some readers, the purpose of my investigation was to conduct an ingame test and share what I found, especially to those that may not know the mechanics of UO.

Good to know, thanks for sharing your results.

Who wrote this for you?

Hahahaha Mobo, you bastard!


Yes Zyler, as they say in Game of Thrones, it is known. If you don't have the 'ability' to 'use' a shield, you're not going to get it's true value. I would be interested to see how much AR gain from a shield increases as you develop Parry skill.
I've never paid attention to the benefit as you develop, but I'd guess it's a gradient.


Queue Dalavar.....

More science please!

Science rules!!

The first thing to remember is that Displayed AR from armor means nothing, in the sense that it is never used in any actual combat damage absorbtion calculation. It's just trying to give you a directional sense of your absorbtion ability. However, for Shields it actually does matter.

Hits on a player strike one of 6 areas, according to a predetermined frequency (i.e. 44% chest, 14% head, etc.). It is only your AR on that area that matters. So for example, if I am wearing a Plate Tunic and nothing else, and you are wearing a full plate suit, 44% of the time someone is going to hit us on the chest and there will be no difference in our ability to absorb the blow... even though your AR is, all the time, much higher than mine.

Parry is checked independently of this. On this shard, your chance to parry is based on the Displayed AR of the shield you have. Chance to block is something like:

[ParrySkill - (AR*2)]. So your store bought heater with 13 AR will give you 100 - 13*2 = 74% chance to block a hit. The amount of damage blocked is based on the Actual AR of the shield. A block will prevent damage equal to half the AR of the shield. So, 74% of hits are blocked by this shield, and they block 13/2 = 6.5 damage per block (I assume this is rounded down to 6).

Here's what is stupid: because your chance to block rises as shield AR goes down, and your amount of damage blocked goes up as your block chance goes down... virtually every shield of a given magic level is the same.

Buckler of Invulnerability, AR 22, blocks 56% of hits, for an average of 11 per block, or 6.2 per hit.
Wooden Shield of Invuln, AR 23, blocks 54% of hits, for an average of 11.5 per block, or 6.2 per hit.
Tear Kite of Invulnerability, AR 25, blocks 50% of hits, for an average of 12.5 per block, or 6.2 per hit.
Metal Kite of Invulnerability, AR 27, blocks 46% of hits, for an average of 13.5 per block, or 6.2 per hit.

Yes, they're all the same. Yay.

The other issue is that the AR provided by shields on this shard is much lower than it was in era. UO Powergamers had a detailed post on this in archive.org. I have the full table, but for brevity...

Buckler (UOR): 4 AR
Buckler (2000): 7 AR
Buckler of Invuln (UOR): 22 AR
Buckler of Invuln (2000): 32 AR
Metal Kite (UOR): 9 AR
Metal Kite (2000): 16 AR
Metal Kite of Invuln (UOR): 27 AR
Metal Kite of Invuln (2000): 41 AR

(edit: proposal in post below)

I should add, I think we can do a bit better job making even more distinction between the shield types, by tinkering with the Base AR of them. The difference between 7 AR of the buckler and 16 AR of the metal kite shield is not terribly large. You could easily make it 4 and 20. And change the damage absorbed to be something other than 50% of the shield AR, if you think the numbers above are too high. But the point is, these are the levers available to make this skill work properly, and further "fix" it if needed.

I'm not one to argue with 4 and 20, so let's make this happen!

Also, aside from damage absorption and chance to effectively parry, the frequency of parry attempts is specific to the shield type, if I'm not mistaken. So while your chances for successful parry may be only marginally different between the sizes, the amount of hits you can potentially parry in a given time frame is decreased as the shield size increases.

I'm not sure what you mean. "chance to effectively parry" and "frequency of parry attempts" mean the same thing to me. And they are not based on the shield type, but rather the AR of the shield.

So, a Buckler of Invulnerability with AR 22, has the sane block frequency of a Metal Kite Shield of Hardening with AR 22. I am arguing that it should be wholly based on shield type, so a store bought buckler should have an 86% chance to block, a GM buckler should have 86%, a buckler of invulnerability should have 86%, etc.

I will continue the investigation by testing the AR value of each shield above with different parry skill levels.

What ya try'n to say?!?

I always loves the idea that there is not one "best shield" around here but instead you could carry multiple shields and equip the one most suitable for the situation.

Telamon, please make it so !

Spent a lot of time playing with numbers, and here's what I think would get the desired results, with the least changes needed.

Change: base AR of shields.



Keep: magical bonus AR of Defense, Invulnerability, etc. This appears to be +18 for Invulnerability.

Keep: chance-to-block formula. This is [ParrySkill - AR/2].

Change: use the Base AR of the shield to determine block percent. That is, 90% chance to block with a store buckler, 90% with a Buckler of Invulnerability. 30% chance to block with a store bought Heater, 30% chance to block with a Heater of Invulnerability.

Change: formula to determine amount of damage blocked. I propose: [AR/(ParrySkill - AR/2)]/4
This is a little abstract, so here is what the numbers would look like in such a scenario (pink is the inputs that my proposal changes from our current system):


What does this mean? It means that the Buckler is a very consistent shield, blocking a little bit of damage from most hits. Against someone with a high-end Katana, a high-end buckler would be a very good choice. It means that the Heater is inconsistent, but when it manages to block, it will shrug off much of the damage from a massive hit. Against someone with a high-end war hammer or halberd, a high-end heater would be a very good choice.

The rest of the shields fall somewhere in between. Maybe metal kite is good against a large battle axe, bronze shield is best for short spears, I dunno. It is up to the player to decide. And hopefully, this will allow parrying to become more viable, and all shield types to be seen in combat situations. Not just an endless parade of heaters.

Finally, these numbers were balanced (in my eyes) by looking at the worst case scenario - everyone running around with invulnerability shields. If people tend to use GM shields, the formula should probably be adjusted a bit. This is extremely easy; just a matter of changing the "4" in the formula below to something like 3 or 3.5:

[AR/(ParrySkill - AR/2)]/4

When I train parry, I get myself surrounded by 8 birds attacking me. I use a buckler because that will effectively parry significantly more often, not just have a slightly better chance of success, but more chances at success.

If, for example, I get 'hit' 50 times a minute by the birds, the buckler will be able to parry more of those hits than a heater shield because of the speed of the shield, not the only the chance of whether you successfully parry or not. If I'm surrounded by a few fencers, I'd likely be able to parry 2/3 of their hits, whereas with a heater I'd maybe parry one. It moves slower so there are fewer chances to parry and more hits will get through because it is too slow to parry them all.

Oh, you're talking about training the skill. Makes sense.

At GM, if you get hit 50 times per minute, and have an 86% block rate with your buckler, you will "try to" and "succeed" at 86% of those hits. To my knowledge, it is NOT the case that you "try to" block 86% of hits, and then there's another dice roll to see if you actually do manage to block it.

Here's the addition of GM Exceptional shields created with valorite ingots into the table, based on the current state of UOR and my proposal formulas above. Purely by luck, I think it fits in very well:

Yeah, not just in training though. If I'm fighting multiple fencers, you better believe I'm pulling a buckler. One LJ? Definitely the heater. Not just chance to hit but amount of swings in a given time frame I can attempt to parry is greater for the smaller shields.

GM a skill AND have the debuff of only using one-hand weapon.
I vote for all changes Dalavar suggested - but a higher damage absorbtion. If i block with my great Heater - what is a low change - it should absorb nearly all damage of good weapons.
Lets say a Battle Axe of Power hits me for 40dmg. It should absorb 25 of it! Hey, its just a 30% chance...

My real UOR-Experience on OSI was: My Parry-Healing Mage roxxored every Dexxer (but sure was not a good duel char against more damage specialised mages).
This was a great skill spec.

-> Absorbed DAmage *1,5 of Dalavars current calculation... and specialised Dexxer-Tanks could (what is not possible now) fight a discordanced Balron with crosshealing This would be nice!

This is not the case. Regardless of the number of swings you are facing, a buckler would block 90% of them and a heater would block 30% of them.

In fact, it would absorb more than 25. A GM Valorite heater would absorb 39, and an Invulnerability heater would absorb 43. The last column in my charts is an overall average across all hits - both those that are blocked, and those that are not.

Again though, if this proves too powerful, or not powerful enough, it is easy to tinker with.