Tested in game by me: 9/15/2017
The reason for this is because I couldn't find an up-to-date values of dice rolls in one place, outside of the game at least. When I tried to searched for it, the information was either outdated and incorrect, or just non-existent.
This guide doesn't have roll percentages, just the effects the dice give.
The skill descriptions are in the skill tab, but here is the brief:
The chart below represents all of the values you can get for rolling specific amount of the same faced dice in one buff usage. The in-game tool-tip will show these same values.
- Roll of the Dice is the main skill of the three; the other two are buffs to it
- All pirates have access to Loaded Dice with 5th job
- Explorer Pirates + Mechanic have access to all three skills, giving them access to roll all three dice
- All other pirates without Roll of the Dice skill gets it from Loaded Dice, but they can only use one die
- The Roll of the Dice skill is found on the 5th job tab, and has a set duration and cooldown of 180 seconds
Die # Buff Effect 1 2 3  Dice cooldown reduction* -90 sec --- ---  Additional defense +30% +40% +50%  Additional HP/MP +20% +30% +40%  Additional critical rate +15% +25% +35%  Additional damage +20% +30% +40%  Additional experience +30% +40% +50%  Additional ignore defense** +20% +30% +40%
*Cooldown based on Roll of the Dice (180 second cooldown)
**Only Buccaneer and Corsair can roll a 7 with their hyper passive, Double Down - Addition
The correlation of having more of the same faces is: Dice Effect plus 10% per die
Here are some example rolls to give you an idea on how the skills work in game:
-  = 30% ignore enemy defense
-  = 30% IED - 90 seconds of cooldown
-  = 90 second cooldown, regardless of how many  you roll.
-  = 20% HP/MP + 30% Defense
-  = 15% crit rate + 20% damage + 20% ignore enemy defense
BuildMax all the dice skills that you have access to.
GameplaySet Loaded Dice to 6 for guaranteed EXP.
Set Loaded Dice to 5 for guaranteed extra damage.
Changelog1.0 guide introduced.
1.1 added Bossing Tab.
1.3 fixed ghetto chart into a real chart.
1.4 added skill info.
1.5 added skill build.
1.6 fixed broken English
1.7 fixed incorrect information about amount of dice