The most important goal is to convert the game to some kind of dice other than d100's. The reason is two-fold: One, to reduce the math to a more manageable level, (whats easier, 87+ 65, or 19+13?) and also because I don't like d100's. The reason I don't like them is because they are clunky, and hard to read or roll multiples of at once regardless of whether you use Zocchihedrons (seen to the right), or just the classic method of 2d10 read as digits. In addition, pretty much all games that use d100's, including Anima, always have their bonuses and penalties measured in increments of 5 anyway.

The truth of the matter is that you pretty much never actually need statistical resolution down to a single percent. 5% is pretty much the smallest increment that anyone is really willing to care about in tabletop gaming.

So then, what kind of dice can we use instead? I have seen some people attempt to convert Anima to using a d10, but I personally think that you lose too much resolution. There are a large number of 5 point bonuses on the 100 point scale, and reducing the game to a d10 requires rounding those up or down.

Because of this, I have chosen to go with d20's. The d20 is always a good substitute for the d100 because it essentially breaks the 100 point scale down into 5 point chunks, which, as I said before, is about as small a difference as anyone really cares about.

Now that we know what kind of number scale were working towards, we can actually get down to the business of converting!

The dice mechanics in Anima come in two forms: Ability Checks and Characteristic Checks.

Ability checks are the most common roll, and involve rolling a d100 and adding your total ability modifier, whether that is an attack roll or a skill check. Ability checks also follow the rules for Open Rolls and Fumbles.

Converting these over to a d20 is fairly simple. We just roll a d20 instead of a d100, and divide all of the ability bonuses and penalties by 5. So if before you had a +90, now you have a +18. The difficulties would of course need to be divided as well.

The Open Roll rule in Anima comes into effect if you roll a natural (as in, the number on the dice) 90 or more. In this situation, you get to roll again, and add the second roll to the total in addition to the first roll. If the second roll can also 'explode', but the number required to explode increases by one each time up to a maximum of 100. For example, if you have an ability of +50, and you roll a 93, you get to roll again. If this roll is a 90, it does not explode again, as you need a 91 on the second roll. Your total in this case would be 233.

Using d20's, I would have the first roll explode on a 19 or a 20 (equivalent to a 90+) and then have the follow up rolls only explode on a 20.

Fumbles in Anima are fairly clunky. Any time you roll a 1, 2, or 3 on your d100, you fumble. In this situation, you roll again, and add a modifier based on what exactly you rolled to produce the fumble. This new total indicates the severity of the fumble. There is also something called

'Mastery'. Mastery comes into effect when your total ability is 200 or more. In this case you reduce your fumbles by 1. meaning you only fumble on a 1 or a 2.

The way I choose to convert/fix this mechanic is very simple:

I remove it.

Critical Fumbles are stupid. They always have been, and always will be. They sabotage your character concepts, and don't really make any sense. The only characters who should ever 'fumble' at something are incompetent douches, and Its pretty rare that anyone wants to play one of those. For my conversion, a 1 will result in a simple failure, nothing more, nothing less. Once a character achieves mastery, then it wont even do that. It will just be a 1, which is bad enough.

Characteristic checks are rolled on a single d10, and use a roll-under mechanic. They are commonly employed in opposed rolls, which function on a weird indirect comparison. (as is often the case with roll-under systems) There is also a special rule for these opposed tests when one ability is greater than the other by more than 4, as well as the 'rule of 1 and 10', which basically says that if you roll a 10, you actually rolled a 13, and if you roll a 1, you actually rolled a -2.

Since we are using d20's now, it seems reasonable to go ahead and change these checks over to d20's, and, while were at it, were going to attempt to convert it to a roll over system as well.

Since the attributes are based on a 10 point scale, the first thing we need to do when converting to a 20 point scale is double them. That way, the proportions of the random element (the die roll) and the fixed element (the characteristic) stay the same. Also, instead of rolling your die, and then comparing it to the characteristic, we will be rolling the die, adding the characteristic, and then comparing it to a fixed threshold.

Before, if you had an average stat (5), you had a 50% chance of success. (roll a 1-5) This means that in our new roll-over system, an average stat should also have a 50% chance of success.

With the new average of 10, the threshold for 50% success would be 21. Its 21, because that means that you need to roll an 11 or better to succeed, which leaves 1-10, half the possible results, as failures.

That works, but I am somewhat tempted to go ahead and lower that threshold to just 20, as that is a bit cleaner, and slightly more intuitive. It does make it easier to succeed on characteristic tests, but honestly, that's not that big of a deal, especially since it will only matter when making unopposed ability checks. When making opposed checks, it will simply be a direct comparison of results.

Now, as for the rule of 1 and 10, I think that we can safely drop that. It doesn't really add that much, and is fairly complicated.

Alright! So here's a summary of what we have today:

- All dice rolls will be made with a d20, rather than a d100.
- All abilities, as well as bonuses and penalties to dice rolls, will be divided by 5.
- Open rolls will initially occur on a natural roll of 19-20, and subsequently only on rolls of 20.
- Fumbles will occur only on a roll of a 1, and only indicate a normal failure regardless of the ability bonus or difficulty. Characters who have achieved mastery of an ability (denoted by having a +40) do not automatically fail, they simply count their die roll as a 1.
- Unopposed Characteristic Checks will be made by rolling a d20 and adding the characteristic being tested. If the total equals or exceeds 20, then the character has succeeded. In opposed characteristic tests, the two characters will simply roll, add their characteristics, and compare their totals. The character with the higher total wins the opposed test.