Perception Rolls

From AaronWiki

Characters aren’t always aware of everything going on around them, especially during combat. Whenever something’s obvious, the GM tells the character about it (“You see a ’67 Chevy in front of you”). But he may require characters to make Perception Rolls (PER Rolls) to notice something inobvious, or to notice something during a combat or crisis situation. Every character’s base PER Roll equals 9 plus his Intelligence divided by 5:

Perception Roll = (9 + (INT/5)) or less

For example, a character with INT 14 has a PER Roll of (9 + (14/5) =) 12 or less.

To make a PER Roll, the character should roll this number or less on 3d6. The GM should apply modifiers to this roll depending on the circumstances (see below).


Many Senses can perceive things at a distance — in other words, they work at Range. For example, characters can see and hear things far away.

The HERO System rules don’t establish any specific outer limit or boundary for a Ranged Sense. However, the Range Modifier (6E2 38) applies to all PER Rolls. In effect, this restricts the Range of a Sense significantly. However, the GM should also establish any other limits that seem appropriate based on common sense, dramatic sense, and considerations of game balance. For example, even if a character on Earth rolls a 3 on his Sight Group PER Roll, he can’t see what’s happening on Mars. As a guideline, when the Range Modifier reaches the point where it reduces a character’s PER Roll to 0 or below, beyond the outer limit of that Range Modifier category things are too blurry, indistinct, or obscured for the character to perceive, even if he rolls a 3.


Of course, not all Senses are equal — a normal human can learn a lot more about someone by looking at him than by smelling him. To reflect this difference, the HERO System divides all Senses into two categories: Targeting and Nontargeting.

A Targeting Sense is a Sense a character can use to determine the exact location of a target. For normal humans, Sight is the only Targeting Sense.

A Nontargeting Sense is one with which the character can, at best, sense the general location of a target. For normal humans, Hearing and Smell are Nontargeting Senses. Taste and Touch both have no range, so characters can’t use them to locate targets at all (to use these Senses, the character would already have to have found his opponent).

Lack Of Senses In Combat

In combat, a character must normally use a Targeting Sense to detect his target. If he can do so, there’s no change in his OCV or DCV, and combat proceeds normally.

However, characters can’t always perceive their opponents with Targeting Senses. For example, a character may have been blinded by a Flash, or his opponent could be Invisible. When a character cannot perceive his opponent with any Targeting Sense, he suffers modifiers to his OCV and DCV:

  • In HTH Combat, the character is at ½ OCV and ½ DCV. This applies both to when he makes attacks in HTH Combat, and is attacked in HTH Combat.
  • In Ranged Combat, the character is at 0 OCV and ½ DCV. This applies both to when he makes attacks in Ranged Combat, and is attacked in Ranged Combat.

If a character can make a PER Roll with a Nontargeting Sense (a Half Phase Action) to perceive a particular target, then against that target only he is at -1 DCV, ½ OCV when attacked or attacking in HTH Combat, and full DCV, ½ OCV when attacked from or attacking at Range. Against all other targets he is affected by the standard “lack of Targeting Sense” modifiers described above. The benefits of making this roll last until the beginning of the character’s next Phase; if he wants them to continue, he has to use another Half Phase Action and succeed with another PER Roll.

Example: Orion, under attack by the supervillain team Eurostar, has been Flashed, and therefore can’t see. He’d normally be ½ DCV, ½ OCV in HTH Combat and ½ DCV, 0 OCV at Range — a sitting duck. However, he makes his Hearing PER Roll against Durak. He’s now only -1 DCV, ½ OCV in HTH Combat and full DCV, ½ OCV at Range against Durak only. He’s still at ½ OCV and DCV in HTH and ½ DCV, 0 OCV at Range against all other opponents.

Moving While Blind

The HERO System rules have no specific penalties or restrictions for moving while a character is blinded (i.e., unable to perceive his surroundings with a Targeting Sense). The GM may impose any penalty he considers appropriate. A character could usually eliminate the penalty by moving slowly (2m per Phase as a Full Phase Action) — that way he can feel his way safely past anything he might trip over or bump into. If a character runs into a sufficiently large object, he may take Move Through damage based solely on his velocity (see Collisions, 6E2 72).