Ambush

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Ambush is the ability to make a very precise attack, employing the element of surprise.

In a hidden ambush, the goal is to approach a target undetected and strike before the quarry can react to defend or strike back. To take advantage of this, one should use the HIDE command (which uses a skill check for Stalking and Hiding) or other means to become hidden, and then, while hidden, make an attack using one of the options detailed below. Ambush skill improves the chance of hitting a specific body part when aiming, and increases critical weighting (with AMBUSH) or damage weighting (with WAYLAY). In addition, the attacker's Ambush skill relative to the target's level will result in decreased defenses, lowering the target's stance for the ambushing attack, which effectively lowers their Defensive Strength (DS). When ambushing with range using FIRE or HURL, only the stance pushdown is applied, not the extra weighting.

In an open ambush, the goal is simply to aim the attack at one of the target's body parts. The chance of hitting the specific body part with melee or hurling is affected by both the Ambush and Combat Maneuvers skills (this is different from hidden ambushes where only Ambush skill is taken into account). For ranged weapons (bows and crossbows), Ambush and Perception are used to determine the chance when firing from hiding, but only Perception is used for open ambushes.

Ambush skill also increases Attack Strength (AS) for all attacks with bows and crossbows, regardless of whether they are aimed or hidden.


Aiming success chance

An initial d100 is made. If you roll <= 5, you auto fumble. If you do not auto fumble, a skill check made:

MIN(95, (Skill + Stats + Weapon Modifier)/2) + Area modifier + Target Status + d100 = Result

Note: Level is not taken into account for aiming success chance. A comparison between Target size and attacker size is included in the area modifier.

Result

> 100: Success
<100 and >66: you miss the location but still find an opening to attack
<=66: You fail to find an opening

Skill

Aiming from hidden = Ambush Bonus

Open aiming = TRUNC((CM Bonus + Ambush Bonus + 1) / 2)

Stats

Dex Bonus + TRUNC(Int Bonus + 1) / 2))

Weapon Modifier

Varies based on weapon. Large/slow weapons have more penalty. Small and maneuverable weapons have a bonus.

Table added at the bottom of the page

Area Modifier

Head: -10
Neck: -15
Arms: +10
Legs: +15
Hands: +5
Eyes: -25
Other: 0
  • Predator's Eye adds into the calculation as part of the location modifier.
  • The area modifier is also modified by attacker/target size. Attacking a target bigger than attacker is easier, a target smaller than attacker is more difficult.

Target Status

Sitting/Prone: +10 if head/neck/eyes, +25 otherwise.


Example

202 CM + Lance (-50 aim) aiming at the head,

 d100 = 84
 Skill = ((302 + 0 + 1) / 2) = 151
 Stats = (20 + (22 + 1) / 2) = 31
 Attacker modifier = 0 
 Weapon Modifier = -50
Result = MIN(95, (Skill + Stats + Weapon Modifier)/2) + Area + Target Status + d100 = max(95, (151 + 31 - 50)/2) - 10 + 0 + 84 = 140
140 > 100 = Success

Ranks and Training Costs

Type Square Semi Pure
Profession Rogue Warrior Monk Bard Paladin Ranger Cleric Empath Savant Sorcerer Wizard
Max Ranks Per Level 2 2 2 1 1 2 1 1 - 1 1
Training Point Cost 2/1 3/4 3/2 4/4 4/5 3/3 12/12 15/15 - 15/14 15/10

Different Ways to Ambush

Entering stealth:

It is also possible to use Invisibility (916), but in practice most creatures will be able to detect invisible player characters.

Attacking from stealth:

In addition, many combat maneuvers have a bonus when initiated from stealth.

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