Active Abilities
Source GM Core pg. 128
Abilities a creature uses on its turn have the most flexibility and scope. You can use the Spell DC and Spell Attack Modifier table on to determine active ability DCs as well as spell DCs. You can have an ability use 1 to 3 actions as needed (or be a free action in rare cases) and use just about any type of tactic. Feats, spells, and existing creature abilities provide a wide variety of examples, so look for something similar to your idea to use as a basis.
Consider how you want your creature to spend its turns. Two-action activities pretty much define the creature's turn, and single actions work best for supplemental benefits or normal Strikes. As you build out your idea of a creature's turn, don't forget about movement! A creature often needs to spend actions getting into position, especially early in a fight. This is especially challenging with melee-focused creatures. You can give such creatures abilities similar to a solarian's Stellar Rush or the void shark's Atmospheric Breach, or even grant it abilities that function like augmentations or armor upgrades from Player Core.Use 3-action abilities sparingly, as a creature can't use them if it's slowed or stunned—making a creature's coolest or most defining ability use up 3 actions might mean the creature never gets to use it. These activities should be reserved for abilities that include some movement (like Trample) or that the creature is likely to use before engaging in combat. Don't make an ability use 3 actions as a way to balance it—saying “This can be more powerful than other abilities because it is less likely to work,” is a recipe for frustration if you've made a cool ability that's too hard or even impossible for the creature to use.
Be especially careful with activities when designing boss creatures. They're likely to get targeted with the PCs' most powerful detrimental effects, get grabbed, become slowed, or otherwise have their actions restricted. Bosses need to have solid options they can use with 1 or 2 actions. This lets them use their remaining actions to get away, use a simple ability, or otherwise keep the fight dynamic.
Consider how you want your creature to spend its turns. Two-action activities pretty much define the creature's turn, and single actions work best for supplemental benefits or normal Strikes. As you build out your idea of a creature's turn, don't forget about movement! A creature often needs to spend actions getting into position, especially early in a fight. This is especially challenging with melee-focused creatures. You can give such creatures abilities similar to a solarian's Stellar Rush or the void shark's Atmospheric Breach, or even grant it abilities that function like augmentations or armor upgrades from Player Core.Use 3-action abilities sparingly, as a creature can't use them if it's slowed or stunned—making a creature's coolest or most defining ability use up 3 actions might mean the creature never gets to use it. These activities should be reserved for abilities that include some movement (like Trample) or that the creature is likely to use before engaging in combat. Don't make an ability use 3 actions as a way to balance it—saying “This can be more powerful than other abilities because it is less likely to work,” is a recipe for frustration if you've made a cool ability that's too hard or even impossible for the creature to use.
Be especially careful with activities when designing boss creatures. They're likely to get targeted with the PCs' most powerful detrimental effects, get grabbed, become slowed, or otherwise have their actions restricted. Bosses need to have solid options they can use with 1 or 2 actions. This lets them use their remaining actions to get away, use a simple ability, or otherwise keep the fight dynamic.
Free Actions
Source GM Core pg. 128
Use free actions that don't have triggers sparingly, and when you do, they should almost always be used for support or utility actions, not Strikes or movement. If you come up with a free action, consider whether it should be its own action or part of a combo, such as drawing a weapon and attacking. In cases like the latter, you might be better off making a single action that allows the creature to draw a weapon and then Strike.
Damage-Dealing Abilities
Source GM Core pg. 128
If a special action is a single action with only one target, you can often set damage using the Strike Damage table. If it uses more than 1 action or requires setup in some way, it might deal higher damage than is typical; often, you can just use the extreme column in these cases.
For abilities that deal damage in an area, use the Area Damage table. These numbers are based on a 2-action activity (e.g., Area Fire and most damaging spells). Single actions should deal much less damage. An ability that has another significant effect, like applying a condition, should deal less damage; for this, look at the damage for 2 or more levels lower, and judge which value would best match based on the severity of the additional effect. These abilities typically allow a basic saving throw. The table includes values for unlimited-use abilities (ones that can be used at will) and limited-use ones (which can be used once or, like dragon breath abilities, once or twice but not on consecutive turns).
You can use the dice given or generate your own expression based on the damage in parentheses, as detailed in the Strike Damage section. If a high-level effect has a small area compared to similar abilities, you could have it deal more damage.
For abilities that deal damage in an area, use the Area Damage table. These numbers are based on a 2-action activity (e.g., Area Fire and most damaging spells). Single actions should deal much less damage. An ability that has another significant effect, like applying a condition, should deal less damage; for this, look at the damage for 2 or more levels lower, and judge which value would best match based on the severity of the additional effect. These abilities typically allow a basic saving throw. The table includes values for unlimited-use abilities (ones that can be used at will) and limited-use ones (which can be used once or, like dragon breath abilities, once or twice but not on consecutive turns).
You can use the dice given or generate your own expression based on the damage in parentheses, as detailed in the Strike Damage section. If a high-level effect has a small area compared to similar abilities, you could have it deal more damage.
Area Damage
| Level | Unlimited Use | Limited Use |
|---|---|---|
| –1 | 1d4 (2) | 1d6 (4) |
| 0 | 1d6 (4) | 1d10 (6) |
| 1 | 2d4 (5) | 2d6 (7) |
| 2 | 2d6 (7) | 3d6 (11) |
| 3 | 2d8 (9) | 4d6 (14) |
| 4 | 3d6 (11) | 5d6 (18) |
| 5 | 2d10 (12) | 6d6 (21) |
| 6 | 4d6 (14) | 7d6 (25) |
| 7 | 4d6 (15) | 8d6 (28) |
| 8 | 5d6 (17) | 9d6 (32) |
| 9 | 5d6 (18) | 10d6 (35) |
| 10 | 6d6 (20) | 11d6 (39) |
| 11 | 6d6 (21) | 12d6 (42) |
| 12 | 5d8 (23) | 13d6 (46) |
| 13 | 7d6 (24) | 14d6 (49) |
| 14 | 4d12 (26) | 15d6 (53) |
| 15 | 6d8 (27) | 16d6 (56) |
| 16 | 8d6 (28) | 17d6 (60) |
| 17 | 8d6 (29) | 18d6 (63) |
| 18 | 9d6 (30) | 19d6 (67) |
| 19 | 7d8 (32) | 20d6 (70) |
| 20 | 6d10 (33) | 21d6 (74) |
| 21 | 10d6 (35) | 22d6 (77) |
| 22 | 8d8 (36) | 23d6 (81) |
| 23 | 11d6 (38) | 24d6 (84) |
| 24 | 11d6 (39) | 25d6 (88) |