| If you are using my Old Imperium style combat rules then the percentage combat tables are a lot smaller because there are fewer combinations to account for. |
| Look up the combination of the attacking ship's beam or missile factor and the defending ship's screen (and for missile attack) countermeasures and if you roll the number to the right of the slash or less on percentile dice the target is destroyed in one shot, otherwise if the roll if less than or equal to the number to the left of the slash the target is merely damaged. |
| Beam factor | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
|---|---|---|---|---|---|---|---|---|---|
| Screen factor 1 | 33/0 | 56/0 | 70/4 | 80/11 | 87/21 | 91/32 | 94/43 | 96/53 | 97/62 |
| Screen factor 2 | 0/0 | 11/0 | 26/0 | 41/0 | 54/0 | 65/0 | 74/1 | 80/2 | 86/4 |
| Screen factor 3 | 0/0 | 0/0 | 4/0 | 11/0 | 21/0 | 32/0 | 43/0 | 53/0 | 62/0 |
| Missile factor | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
|---|---|---|---|---|---|---|---|---|---|
| Screen 1 + CM 0 | 33/0 | 56/0 | 70/4 | 80/11 | 87/21 | 91/32 | 94/43 | 96/53 | 97/62 |
| Screen 1 + CM 1 | 22/0 | 41/0 | 56/2 | 67/8 | 76/16 | 82/25 | 87/34 | 91/44 | 93/53 |
| Screen 1 + CM 2 | 16/0 | 32/0 | 45/2 | 57/6 | 67/12 | 74/20 | 80/29 | 85/37 | 89/46 |
| Screen 1 + CM 3 | 14/0 | 27/0 | 39/2 | 49/5 | 59/10 | 67/17 | 74/25 | 79/33 | 84/41 |
| Screen 2 + CM 1 | 0/0 | 7/0 | 19/0 | 31/0 | 43/0 | 54/0 | 63/0 | 71/1 | 78/3 |
| Screen 2 + CM 2 | 0/0 | 5/0 | 14/0 | 25/0 | 35/0 | 46/0 | 55/0 | 64/1 | 71/2 |
| Screen 2 + CM 3 | 0/0 | 5/0 | 12/0 | 21/0 | 30/0 | 40/0 | 49/0 | 57/1 | 64/2 |
| Screen 3 + CM 3 | 0/0 | 0/0 | 2/0 | 5/0 | 10/0 | 17/0 | 25/0 | 33/0 | 41/0 |
| Screen 3 + CM 4 | 0/0 | 0/0 | 1/0 | 5/0 | 9/0 | 15/0 | 22/0 | 29/0 | 36/0 |
-HJC