Brace to Fire

## Basic Concept

*Brace to Fire*, or *Tubthumping*, is a mechanic which makes large bore ballistic weapons and artillery have a chance to cause a self knock down of the firing 'Mech. Any firing of weapons with this feature enabled will trigger a roll against the combined knockdown chance of the weapons.

### **AI**

Due to the complexity of the AI in the game there was no way to make it understand the concept of Brace to Fire, and as such you will often see it falling over very easily after firing such weapons at lower difficulty levels.

However, to mitigate this problem at higher levels - and especially for Kill Teams lances - the AI can gain some special resistances to the knockdown, this is **not a bug**.

## Chance for Knockdown

The base chance of knockdown per weapon fired varies based on the weapon type and size, but generally the larger weapon and the more damage it can do, the higher the chance. If the weapon is capable of multiple firing modes, the general rule is the more or larger shots fired in the same attack, the higher the increase in knockdown chance.

The chance is listed in the weapon's tooltip and on the wiki (if the weapon is not marked as classified). If you encounter a weapon missing the chance in the tooltip yet causing tubthumping knockdowns, report it to the developers as it is a bug.

Example knockdown chances
 Spinal Mount HGR

#### Mitigating Knockdown Chance

There are several ways to mitigate the chance of a knockdown:

* **Brace previous turn** - The main way to mitigate the knockdown risk is to **Brace** the round before and not move the current turn before firing the weapons. This provides enough reduction of the knockdown chance to practically be immune, except in the most extreme cases. The actual reduction is -100% chance for knockdown. **Rotating the 'Mech before firing does not count as a movement.**

* **MechWarrior Piloting Skill** - Every level of the **Piloting** skill the MechWarrior operating the 'Mech has, the chance of a knockdown is reduced by 1%.

* **Equipment or Quirks** - There are several types of equipment, such as Gyros and Superheavy Frames, as well as Quirks that lower the chance of a knockdown.

* **Special types of Mechs** - All QuadMechs inherently reduce the chance of a knockdown by 30% base, and entering a QuadMech's *Siege Mode* reduces the final value by another -25% (applied after all other modifiers). Quadvees reduce the chance of knockdown by 25%.

* **Chassis tonnage weight** - The higher the tonnage of the 'Mech mounting the weapon, the lower the chance of a knockdown is. See the table below.

* **Vehicle** - All vehicles are inherently immune to knockdown from firing weapons.

The following graph and table shows the base reduction of Knockdown chance by the 'Mech's tonnage. For 'Mechs above 100 tons (Superheavy), the reduction includes the value from the *Superheavy Frame*.

1) Includes Superheavy Frame

## Actual Maths

These are the actual formulas to calculate the actual Knockdown chance after firing. They are mainly provided as an extra, and will not be explained in detail by the Roguetech Crew even if asked directly.

```
 Weapons: Combined Value of all Weapons firing with Knockdown chance (Additive, can exceed 100%)
 Brace: If braced previous turn and no movement this turn => -100%
 Piloting: Piloting Level x 1%
 Tonnage: Mech Tonnage x 0.15%
 Tonnage Bonus: Mech Tonnage > 100 => Mech Tonnage x 0.1%
 Equipment: The combined reduction to Knockdown chance of all equipment (Additive)

```

```
 Knockdown Chance = Weapons - (Brace + Piloting + Tonnage + Bonus + Equipment)

```