Editing Item drops
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===Monsters=== | ===Monsters=== | ||
Each time | Each time an enemy is defeated, the game rolls to determine whether an item will drop, and if so, what that item will be in the following order: | ||
#The game rolls for event drops, such as {{Tool|rare|Event Egg}}, {{Tool|rare|Halloween Cookie}}, or {{Tool|Present (Christmas)}} | #The game rolls for event drops, such as {{Tool|rare|Event Egg}}, {{Tool|rare|Halloween Cookie}}, or {{Tool|Present (Christmas)}} | ||
#The game rolls for [[music disks]] (<code>1/600</code> from any | #The game rolls for [[music disks]] (<code>1/600</code> from any enemy) | ||
#The game rolls based on the | #The game rolls based on the enemy's [[drop anything rate]] (DAR) to determine if the enemy has the possibility of dropping anything else | ||
#The game rolls to decide if the | #The game rolls to decide if the enemy will drop its specified rare item (depending on area, section ID, and difficulty) | ||
#The game rolls to determine whether the drop is {{Meseta}}, a [[tools|tool]], or the | #The game rolls to determine whether the drop is {{Meseta}}, a [[tools|tool]], or the enemy's set drop. Each of these categories has an equivalent <code>1/3</code> chance of being rolled | ||
The chance to obtain items from enemies can be increased with drop rate boosts. DAR boosts increase the chance to obtain any item at all from monsters, which can also help with its designated rare drop. [[Rare drop rate]] (RDR) boosts only increase the chance for the designated rare drop. However, a monster can't have more than 100% DAR. Certain monsters already have 100% (bosses, rare enemies) or otherwise high DAR, meaning strong DAR boosts like the 25% weekly boost won't have their full effect. A similar rule applies to RDR, in which the maximum RDR can only be boosted to <code>7/8 (87.50%)</code>. This, however, applies to very few monsters (e.g. rare Rappies from VR Temple). | |||
The chance to obtain items from | |||
===Item box=== | ===Item box=== | ||
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* Roll for music disk fails: <code>1 - 1/600 = '''599/600'''</code> | * Roll for music disk fails: <code>1 - 1/600 = '''599/600'''</code> | ||
* DAR roll successful: <code>'''3/10''' (30%)</code> | * DAR roll successful: <code>'''3/10''' (30%)</code> | ||
* RDR roll fails: <code>1 - 1/64 = ''' | * RDR roll fails: <code>1 - 1/64 = '''59/64'''</code> | ||
* Roll for set drop successful: <code>'''1/3'''</code> | * Roll for set drop successful: <code>'''1/3'''</code> | ||
The overall chance can now be calculated by multiplying the above rates: | The overall chance can now be calculated by multiplying the above rates: | ||
<code>499/500 * 599/600 * 3/10 * | <code>499/500 * 599/600 * 3/10 * 59/64 * 1/3 = '''1/10.89 (9.18%)'''</code> | ||
From this point, further calculations can be performed in a similar fashion to determine more specific drop rates, e.g. which weapon will drop and with what attributes (see [[weapon attribute drop tables]] for further information). | From this point, further calculations can be performed in a similar fashion to determine more specific drop rates, e.g. which weapon will drop and with what attributes (see [[weapon attribute drop tables]] for further information). | ||
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The overall chance of obtaining items by killing several monsters or destroying several boxes can also be calculated. For multiple rolls, the overall chance to receive a drop naturally increases. However, this increase is not linear. The increase is determined by following the binomial distribution formula: | The overall chance of obtaining items by killing several monsters or destroying several boxes can also be calculated. For multiple rolls, the overall chance to receive a drop naturally increases. However, this increase is not linear. The increase is determined by following the binomial distribution formula: | ||
<code>''chance of at least | <code>''chance of at least 1 drop'' = 1 - (1 - ''drop rate'') ^ (''number of events'')</code> | ||
Using the above example, the overall chance of receiving at least 1 weapon box from a Claw by killing it '''10''' times is: | Using the above example, the overall chance of receiving at least 1 weapon box from a Claw by killing it '''10''' times is: | ||
<code>''chance of at least | <code>''chance of at least 1 drop'' = 1 - (1 - ''1/10.89'') ^ (''10'') = '''1/1.62 (61.83%)'''</code> | ||
Killing more enemies naturally increases the likelihood of receiving an item, but it will never be 100% guaranteed. This is contrary to the popular belief that killing a monster <code>X</code> times for its <code>1/X</code> item drop will give you a guaranteed drop. In reality, the overall chance in this case always comes out to roughly <code>'''63%'''</code> (approaching <code>1 - 1/e</code>, where e = Euler's number). This is statistically defined as the average chance where at least 1 drop will occur, and is particularly useful when performing calculations such as "how many runs will it take to get this item?" | Killing more enemies naturally increases the likelihood of receiving an item, but it will never be 100% guaranteed. This is contrary to the popular belief that killing a monster <code>X</code> times for its <code>1/X</code> item drop will give you a guaranteed drop. In reality, the overall chance in this case always comes out to roughly <code>'''63%'''</code> (approaching <code>1 - 1/e</code>, where e = Euler's number). This is statistically defined as the average chance where at least 1 drop will occur, and is particularly useful when performing calculations such as "how many runs will it take to get this item?" | ||
====Combined drop rates==== | =====Combined drop rates===== | ||
Some monsters drop the same item but with different drop rates. For a drop rate <code>A</code> and a drop rate <code>B</code> the combined drop rate <code>C</code> is: | Some monsters drop the same item but with different drop rates. For a drop rate <code>A</code> and a drop rate <code>B</code> the combined drop rate <code>C</code> is: | ||
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For instance, if one enemy drops an item with a drop rate of <code>1/2</code> and another with a drop rate of <code>1/4</code>, the overall chance of receiving at least 1 drop from killing both monsters is: | For instance, if one enemy drops an item with a drop rate of <code>1/2</code> and another with a drop rate of <code>1/4</code>, the overall chance of receiving at least 1 drop from killing both monsters is: | ||
<code>1/2 + 1/4 - 1/2 * 1/4 = '''1/1.6 | <code>1/2 + 1/4 - 1/2 * 1/4 = '''1/1.6''' (62.5%)</code> | ||
{{Guides}} | {{Guides}} | ||
[[Category:Guides]] |