Help with Dice Rolling

Hello, I have recently started an Anima:Beyond Fantasy campaign in roll20 which uses 1d100 dice which isn't a problem. However, the problem comes from a type of exploding dice, in that the rules state on a roll equal to or above a value of 90 the dice are rolled again and added together, but the second roll now only gets an additional roll on a value of 91 or higher. This decrease continues if additional rolls keep happening until only a value of 100 gets another roll. Example: roll 1d100, get 95, reroll 1d100, get 90, don't get another roll so total is 90+95=185 I have looked in the dice wiki, and have tried many combinations, but I can't seem to get this formula down. Any help would be appreciated if someone can figure out a way to do this with the dice.

I believe you will have to do your rerolls manually since we have no kind of graduating reroll scale like this. Alternately, you can roll 10d100 and just take them in order. But again the addition would be manual.  Finally, I would talk to the API guys in the API forum. See if they can come up with anything.  - Gauss

Ok, I appreciate it, just thought I would ask to see if someone had a formula, manually can work if we have to.

The API could do this fairly easily.    I've been away from Roll20 for a few weeks and still am busy, but I'll see if I can whip something up.  But you would have to be a mentor to use the script (the GM would have to be).