A multiplier is generally some number a different number is multiplied with to get a new number. For our VS Battles use we more specifically refer to a number as multiplier, if that number is multiplied with some statistic of a character or its attacks to get a new statistic for the character.
The use of multipliers to gain new statistics is usually a controversially debated topic. The reason for that is that it allows characters to be evaluated as significantly more powerful, without ever demonstrating that degree of power in a confirmable way.
As such several guidelines are in place, which regulate multiplier use:
Multipliers come from direct statements instead of being reasoned from something else. That means, for example, that if a verse has powerlevels or statistics, the doubling of a statistic or power level should not be concluded to correspond to the power of the character doubling, unless it is clearly specified to work that way.
The statements a multiplier is based on must always be reliable.
One should also consider which statistic a multiplier applies to. If a character just gets 10 times more powerful, then that doesn't necessarily means that all of its statistics are multiplied by 10. For example could a fiction in principle have a character become a 10 times more dangerous fighter just by increasing his combat technique, with only minor increases in stats. A more classical scenario is one where a characters strength increases by some multiplier, but its speed is untouched.
However, a good statement alone is not enough to get a high multiplier accepted. The amount of extra evidence one has to provide to get larger multipliers accepted is proportional to the size of the multiplier. For lower multipliers, like things much less than times 100, evidence can take the form of a clear increase in combat strength against priorly equal or superior opponents. For higher multipliers, like times 100 and above, the importance of stronger evidence, such as feats displaying power of a similar magnitude as the value the multiplier points to or the multipliers importance to the plot of the story, and a higher amount of evidence becomes increasingly necessary.
If multiple multipliers are to be stacked, that are used upon each other, the evidence for the end result is equal to the total multiplier applied to the best feat. That means that if, for example, a character has a times 10 multiplier and later on gets another times 50 multiplier, than the evidence necessary to use both multipliers to get a statistic, is like that of a times 500 multiplier, as the best feat would be increased by a factor of 500 in that case.
In regards to multiplier stacking one should also pay attention to whether a multiplier applies to the strength of the character without the other multipliers applied or with the other multipliers already applied.
Multipliers in games get some special attention, due to the fact that they are often Game Mechanics. For example games often consider multipliers as just a different form of extra damage, like when they have multipliers on headshots and critical hits. As such there should be at least some indication that a multiplier on a move or an item in game also corresponds to a multiplier in the games story.
Another thing to keep in mind is that multipliers are not necessarily constant. For example: If a character is twice as fast as another at one point in time, that might not apply at any other point in time. Likewise if a technique is at one point twice as strong as another, that might change when the mastery of the techniques changes.
Aside from such considerations, if it comes to techniques which divide the power of an opponents attacks by something or multiplies the strength of an allies attacks feats will be necessary, regarding what the strongest attacks are for which this works. The reason for that can be easily seen by example: Doubling the power of a 10 Tons of TNT attack requires just the addition of further 10 Tons of TNT. Doubling the power of a 100 Tons of TNT attack requires adding 100 Tons of TNT on the other hand. That means doing that for the 100 Tons of TNT attack requires a far more powerful technique.
Lastly, multipliers will obviously only be used if they are not contradicted. A typical case of that would be if a character gets 10 times stronger, but fighters that were previously equal to it can still somehow keep up.
For combination attacks, similar standards to multipliers apply. It should not be assumed that a combination attack performed by multiple characters has Attack Potency equal to the sum of the participating characters Attack Potency unless there is specific evidence for it.
For better judgement on how much evidence one should bring if one wishes a multiplier to be accepted, and to decrease double standards as much as possible, one can look at the following precedent cases.
Multipliers without reliable statements
- Dragon Ball Super Saiyan Multipliers: Rejected due to never being stated in the actual series. Furthermore often seem to multiply in-universe power levels and not actual power. They often seem inconsistent, like for example the x2 SSJ2 multiplier turning a stomp around.
- Kuroi Seishi: Rejected due to merging with 1 billion of his clones and yet despite this, is still on the level of Tatsumaki.
Low Accepted Multipliers
- Nanatsu no Taizai, Supreme Being and Demon King Multipliers: Accepted due to being consistent with feats, but straight and to the point while also being quite a small, but reasonable multiplier. Also is consistent in lore.
- Katekyo Hitman Reborn Dying Will Flame Multipliers: Accepted due to being consistently portrayed and stated by reliable sources. It is clear what is being multiplied, as Dying Will Flames increase physical statistics (speed and power), and are also small but reasonable. Stated multipliers are also shown by consistent showings.
High Accepted Multipliers
- The God of High School, 250,000x Multiplier: Accepted due to having no contradictions within the series, and only applying to the god tiers of the verse. Every multiplier performed in the series was either used to stomp the opposition, or even the playing field against someone who was previously stomping. The 250,000x multiplier itself was used by Mori Jin to completely overwhelm Satan, who was previously physically overpowering him.