Magic Item Failure / Breakage

Magic Item Failure / Breakage

sivousplay 08 Sep 2009 00:01

A masterwork item can be infused with magical energies to be made more powerful, but since the Affliction, the magical energies within the world are much harder to control and magical items can fail or break on use.

The mechanism for this is still pretty shaky, but here's a start …

At the end each round of combat (or after a non-combat use of an item), each player draws a card from the tarot deck to determine how their magic items performed during the previous round:

Suit - Relevance
Swords - Melee Weapons
Spears - Ranged Weapons (including wands, staves, and any magical focus item)
Shields - Armor, Shields, any protection magic (capes, rings, etc).
Cups - Misc magic not covered by the above
Major Arcana - special … probably will create a table for these

Card Value - Result
2,3,4,5,6 - failure (for the # of rounds of the card value)
7,8,9,10 - breakage (repair cost equal to item plus * card value * 500 gp; repair time required is a card value * d4 number of days)
P,Kn,Q,K,A - no failure or breakage

When an item has failed, the item still functions as a masterwork item of its kind, but no magical properties are available. When an item breaks, it does not function in any capacity until it is repaired.

Examples

If Gabriel has a +3 Holy Longsword and after attacking a green dragon in battle, draws the 4 of Swords, his magical sword has failed and for the next 4 rounds will function as a masterwork longsword, but the +3 bonus is lost and the Holy special ability can not be used.

If Gabriel has a +3 Holy Longsword and after attacking a green dragon in battle, draws the 8 of Swords, his magical sword has broken and until he finds a magical swordsmith capable of repairing the sword and provides the swordsmith with materials valued at 5 (holy(+2) +3 = +5) * 8 (card value) * 500 = 20,000 gp and the repair will take 8d4 days to repair.

Last edited on 08 Sep 2009 00:21 by sivousplay Show more

Re: Magic Item Failure / Breakage

sivousplay 08 Sep 2009 00:08

As you can see, combat will be dangerous … not only for the player(s), but for their magical items as well. I think this will cause players to more carefully consider which combats to enter and for that matter which items to use in combat. If you think you can win a combat without endangering you special item, maybe you will do that … could make more mundane encounters more challenging as the party backs off / avoids using their best gear.

Still trying to decide what the best mechanism for item selection (when more than one of a kind are in use). Might just let the player select and move on …although that might take forever!! :)

Re: Magic Item Failure / Breakage

qbalrog 08 Sep 2009 01:39

May need to play this a little; not sure if the proportions are right. I guess it depends if folks will always have an item of each type or not. If they do, that means a 1/3 chance of breakage each round or for a battle of 3-4 rounds, only a 1 in 5 chance of no breakage? Might be a little too much. Put another way, with breakage chance that high, you just won't think of any magic as permanent and it will have, therefore, much lower value. Maybe that's what you want :)

Might also be more fun if everyone draws a card at start of round and reveals it after they declare their action.

One downside of this: it's a lot of cards out at once and maybe a lot for you to do if you are doing it for your NPCs. Alternately, there could be one card drawn for everybody per round.

Re: Magic Item Failure / Breakage

sivousplay 08 Sep 2009 03:31

You are probably right on the percentages and the overhead … however, I do want magic to be something that is marginally understood/elusive/fragile/complicated (like technology in the mad max world).

Nonetheless, I think the odds are too high as described and the overhead too complex … maybe we just draw one card and roll a d20 … the d20 represents the position (modulo 20) on the initiative chart whose items risk failure/breakage … now you have a 1/20 factor on top of the odds you calculated and it's one card and one die roll … much less overhead (and w/ it being based on the initiative chart, it's an easy reminder when I have to do it for the bad guys). Stuff is still going to break, but only often enough to remind you that you can't count on magic.

??

Last edited on 08 Sep 2009 03:32 by sivousplay Show more

Re: Magic Item Failure / Breakage

qbalrog 08 Sep 2009 03:41

Was thinking about this more and I think your method as described is the right approach. Doing a card with someone's action is just going to slow down already slow game play. Doing it at end of round can be quick and easy. Might not be much trouble for the ref since you only need to draw cards for NPCs using magic items.

One thing you might want to change is to allow item damage, like in Fallout. It requires more bookkeeping on the player's part but it has the virtue of making them chose whether to stop using an item before it breaks.

So: suit cards determine item type (as above)
suit rank: 2-5 causes that much damage out of 10, 6-10 completely broken; J-A no damage (or maybe extra effect at the cost of 1-4 damage?).
Major arcana could do things like item doesn't work for x rounds and other possibilities.

As for selecting an item, I think you should roll among any items of the suit-type that are equipped. In order to minimize possible exploit where someone equips a lot of items just to minimize the chance of a failure of a prized item, maybe some of the arcana can deal with "overload" which is a function of total number of items equipped. I.e., have too many items equipped and they all blow up :P

Item damage is a bit of bookkeeping but it adds another dimension to the whole thing. Then maybe something like this for repairs:

Repair damage at (damage level)/20*(standard cost of an item).
Repair broken item at (standard cost of an item).
Create a new item from scratch 2*(standard cost of an item).

With this cost, there is always benefit for keeping an item functional. At 9 damage, repair is 0.45 create cost. At broken it is 1.0 create cost to fix.

This makes item creation even more expensive but makes the creation feats still of interest. In this case, though, maybe repair does not take XP? Just money? If it takes XP I bet only NPCs repair anyway. If you don't make it take XP, might get more PCs taking it. (For instance, only casters can likely take item creation feats and they aren't going to repair someone's sword if it takes XP; or if they do, it isn't really all that fair to them).

Re: Magic Item Failure / Breakage

sivousplay 08 Sep 2009 04:08

I thought about the HPs/damage points for items idea and wasn't sure if folks would be ok w/ the bookkeeping or not … that means you'd have to tally it for every magic item you possess, but I do like the options it gives the player about choosing to use an item or not; however, I'm inclined to require ranks in appraisal to perfectly assess when the item will fail … not sure what the mechanism might be offhand, but I think a little inaccuracy on the HPs of the item would be more inline with my notions about magic in this world.

Re: Magic Item Failure / Breakage

qbalrog 08 Sep 2009 06:20

I think the HP is worth trouble. Not sure how practical keeping it hidden will be since the players will be tallying the damage. I think you'd have to use an uncertainty principle. Players track the damage and, if the uncertainty is say +/-2, when the damage was at 8, you'd need to roll to see if it was actually 10 (20% chance), etc. At 9 25% chance, at 10, 33% chance, at 11 66% etc. Although I'd need to double check my conditional probability. Maybe that's actually wrong.

It might be easiest to stick with a card per player and just adjust the values that cause failures to get the overall probability you want. One card then a player determination roll versus a card per player: the latter is probably faster once people understand what the cards do. And it allows for multiple failures in a round.

What about:
Suit ranks: 2-5 causes damage, Ace or King outright failure, rest no effect? or something like that. Then would need to do the 22 major arcana in a chart of some sort.

Re: Magic Item Failure / Breakage

sivousplay 08 Sep 2009 17:06

I was thinking through the math … if I did it correctly, your proposed scheme feels pretty good …

2-5 cause dmg is 14 pts of dmg / 14 cards per suit … so on average (ignoring major arcana effects), a player will have a magic item from one of the 4 categories take 1 pt of dmg per round. With 10 dmg points for an item and 4 categories, it means on average an item will last 40 rounds of combat. If you figure the average combat lasts 4 rounds, then in 10 combats, an item of each type will be approaching breakage. At 3-5 combats per night, it means an item will need repair every 2-3 sessions. If the players level every 3-5 sessions, it means a magic item will last 1/2 - 1 full level before it needs repair.

Adding outright failure on an Ace, increases that, but I like the idea of outright failure. I also like the idea of a temporary failure with no dmg taken (represents the … how the hell does this magic stuff work anyways????) …

So, I'm proposing each player draws a card after a round of combat or after a non-combat use of an item. (When multiple items in a category are equipped, I think I'll just create a chart and do a single roll with outcomes like, main equipped, backup, etc which will apply to everyone … having each player roll a die and say which roll represents which item will take forever at higher levels with more items equipped).

2-5 causes damage, Ace is automatic failure, K causes temporary failure for 1d4 rounds. All other cards have no effect. Major Arcana will have special effects … some good / some bad.

Repair as you suggested … I like having the craft skills be useful and I think the costs you outlined seems reasonable and no XP costs to repair, just to craft initially.

Re: Magic Item Failure / Breakage

qbalrog 08 Sep 2009 19:13

Sounds very interesting- damage, out-right breakage and temparorily not working.

I think the way to look at it is rounds to failure like the charts I added below. We can adjust the outright failure rate and my charts don't comprehend damage but for a first order, I think you could consider damage as a fractional chance of failure (i.e. if there is a 10% chance of 25% damage, it roughly increases the breakage rate by 0.1*0.25 -> 2.5%)

Need to figure out how often you want an item to outright break and then arrange the card chart accordingly. Once we have something more refined, I will run some simulations to get a feel for rounds until breakage.

It depends how much magic you expect us to possess at any time. For example: if we are getting an item every 2 battles and battles last ~4 rounds, then a breakage every 8 rounds or so might be appropriate. Maybe 8-10% breakage rate (assuming damage is factored into the overall failure rate).

Re: Magic Item Failure / Breakage

qbalrog 08 Sep 2009 19:06

Here's the chance of a N items being broken for various failure rates per round. Assumes only one item can fail per round. I can easily work up other failure rates but basically need to pick a rate that corresponds to how often we want something to break. For instance, one broken item every six rounds requires about an 12% failure rate: 12% of the cards would have to result in a break.

In the tables columns are rounds of combat and rows are number of items broken.

25% chance of failure

	1	2	3	4	5	6	7	8	9	10
0	75.00%	56.25%	42.19%	31.64%	23.73%	17.80%	13.35%	10.01%	7.51%	5.63%
1	25.00%	37.50%	42.19%	42.19%	39.55%	35.60%	31.15%	26.70%	22.53%	18.77%
2		6.25%	14.06%	21.09%	26.37%	29.66%	31.15%	31.15%	30.03%	28.16%
3			1.56%	4.69%	8.79%	13.18%	17.30%	20.76%	23.36%	25.03%
4				0.39%	1.46%	3.30%	5.77%	8.65%	11.68%	14.60%
5					0.10%	0.44%	1.15%	2.31%	3.89%	5.84%
6						0.02%	0.13%	0.38%	0.87%	1.62%
7							0.01%	0.04%	0.12%	0.31%
8								0.00%	0.01%	0.04%
9									0.00%	0.00%
10										0.00%
Median Failed Items	0	0	1	1	1	1	2	2	2	2

12% chance of failure

	1	2	3	4	5	6	7	8	9	10
0	88.00%	77.44%	68.15%	59.97%	52.77%	46.44%	40.87%	35.96%	31.65%	27.85%
1	12.00%	21.12%	27.88%	32.71%	35.98%	38.00%	39.01%	39.23%	38.84%	37.98%
2		1.44%	3.80%	6.69%	9.81%	12.95%	15.96%	18.72%	21.19%	23.30%
3			0.17%	0.61%	1.34%	2.36%	3.63%	5.11%	6.74%	8.47%
4				0.02%	0.09%	0.24%	0.49%	0.87%	1.38%	2.02%
5					0.00%	0.01%	0.04%	0.09%	0.19%	0.33%
6						0.00%	0.00%	0.01%	0.02%	0.04%
7							0.00%	0.00%	0.00%	0.00%
8								0.00%	0.00%	0.00%
9									0.00%	0.00%
10										0.00%
Median Failed Items	0	0	0	0	0	1	1	1	1	1

8% chance of failure

	1	2	3	4	5	6	7	8	9	10
0	92.00%	84.64%	77.87%	71.64%	65.91%	60.64%	55.78%	51.32%	47.22%	43.44%
1	8.00%	14.72%	20.31%	24.92%	28.66%	31.64%	33.96%	35.70%	36.95%	37.77%
2		0.64%	1.77%	3.25%	4.98%	6.88%	8.86%	10.87%	12.85%	14.78%
3			0.05%	0.19%	0.43%	0.80%	1.28%	1.89%	2.61%	3.43%
4				0.00%	0.02%	0.05%	0.11%	0.21%	0.34%	0.52%
5					0.00%	0.00%	0.01%	0.01%	0.03%	0.05%
6						0.00%	0.00%	0.00%	0.00%	0.00%
7							0.00%	0.00%	0.00%	0.00%
8								0.00%	0.00%	0.00%
9									0.00%	0.00%
10										0.00%
Median Failed Items	0	0	0	0	0	0	0	0	1	1

4% chance of failure

	1	2	3	4	5	6	7	8	9	10
0	96.00%	92.16%	88.47%	84.93%	81.54%	78.28%	75.14%	72.14%	69.25%	66.48%
1	4.00%	7.68%	11.06%	14.16%	16.99%	19.57%	21.92%	24.05%	25.97%	27.70%
2		0.16%	0.46%	0.88%	1.42%	2.04%	2.74%	3.51%	4.33%	5.19%
3			0.01%	0.02%	0.06%	0.11%	0.19%	0.29%	0.42%	0.58%
4				0.00%	0.00%	0.00%	0.01%	0.02%	0.03%	0.04%
5					0.00%	0.00%	0.00%	0.00%	0.00%	0.00%
6						0.00%	0.00%	0.00%	0.00%	0.00%
7							0.00%	0.00%	0.00%	0.00%
8								0.00%	0.00%	0.00%
9									0.00%	0.00%
10										0.00%
Median Failed Items	0	0	0	0	0	0	0	0	0	0

Last edited on 08 Sep 2009 19:15 by qbalrog Show more

Re: Magic Item Failure / Breakage

sivousplay 08 Sep 2009 20:22

So, if this is math is correct …

For the dmg cards, you get 1/14*2/10 + 1/14*3/10 + 1/14*4/10 + 1/14*5/10 = 1/14 * 1.4 = 10% failure rate

For the outright failure you have 1/14 = 7.14% failure rate.

Combining these results in an expected lifetime of approximately 6 combat rounds for an item; however with the 1/4 chance of drawing any suit, the lifetime should be extended to ~24 rounds, but at that point an item in each category would be at the breaking point. I think.

Did I do that right?