Depends on how small the dice are and how many you roll.
2d4
1-1
1-2
1-3
1-4
2-2
2-3
2-4
3-3
3-4
4-4
Chance to roll a double, approx: 40%.
2d6
1-1
1-2
1-3
1-4
1-5
1-6
2-2
2-3
2-4
2-5
2-6
3-3
3-4
3-5
3-6
4-4
4-5
4-6
5-5
5-6
6-6
Chances to roll doubles: approx. 28.57%
2d8
1-1
1-2
1-3
1-4
1-5
1-6
1-7
1-8
2-2
2-3
2-4
2-5
2-6
2-7
2-8
3-3
3-4
3-5
3-6
3-7
3-8
4-4
4-5
4-6
4-7
4-8
5-5
5-6
5-7
5-8
6-6
6-7
6-8
7-7
7-8
8-8
Chance to roll doubles: approx 22.22%
2d10
1-1
1-2
1-3
1-4
1-5
1-6
1-7
1-8
1-9
1-10
2-2
2-3
2-4
2-5
2-6
2-7
2-8
2-9
2-10
3-3
3-4
3-5
3-6
3-7
3-8
3-9
3-10
4-4
4-5
4-6
4-7
4-8
4-9
4-10
5-5
5-6
5-7
5-8
5-9
5-10
6-6
6-7
6-8
6-9
6-10
7-7
7-8
7-9
7-10
8-8
8-9
8-10
9-9
9-10
10-10
chances to roll doubles: approx. 18.18%
2d12
1-1
1-2
1-3
1-4
1-5
1-6
1-7
1-8
1-9
1-10
1-11
1-12
2-2
2-3
2-4
2-5
2-6
2-7
2-8
2-9
2-10
2-11
2-12
3-3
3-4
3-5
3-6
3-7
3-8
3-9
3-10
3-11
3-12
4-4
4-5
4-6
4-7
4-8
4-9
4-10
4-11
4-12
5-5
5-6
5-7
5-8
5-9
5-10
5-11
5-12
6-6
6-7
6-8
6-9
6-10
6-11
6-12
7-7
7-8
7-9
7-10
7-11
7-12
8-8
8-9
8-10
8-11
8-12
9-9
9-10
9-11
9-12
10-10
10-11
10-12
11-11
11-12
12-12
chances to roll doubles: approx. 15.38%
granted, mixing and adding dice will change those chances somewhat, but so far, I think this system has merits... also, keep in mind that the higher that double is, the worst it will be. so, while that d4 might increase your chances to roll a double, this double will be relatively low.
Last edited July 26, 2016 4:27 pm