# VELOCITY-BASED MOVEMENT FOR THE HERO SYSTEM

## MOTIVATION

This is an article on a new system I have for velocity and movement in the Hero system. It replaces some already existing rules, and costs -- thus it requires some conversion of existing characters. However, I think that it addresses many problems with the current system.

In many ways, I was dissatisfied in many ways with the way velocity and in particular velocity-based damage were handled in the Hero system. Some odd points I have noticed are:

• Move-Through and Move-By damage can be abusive to game balance. For example, a STR 50 character with 26'' of Running can do 19d6 damage with a move-through, even though each power is only 40 active points.
• Damage due to non-combat velocity move-throughs is rather unbelievable when compared to other attacks. For example, a Cadillac going at only 30 MPH does 20d6, which is more DC's than a howitzer!
• The damage is based on a game artifact of inches per phase, rather than on velocity in real-world terms like MPH. For example, two vehicles of the same mass are moving at the same speed in MPH. The less maneuverable one (i.e. lower SPD) does much greater damage, because it has more inches per phase.
• Throwing doesn't scale right for high strength. For example, a character can lift a tank (55STR) and move at supersonic speeds, but with a standing throw he cannot throw a football the length of a football field (100 meters).

My system is intended to be a fix to all of the above and more. It does rely on use of a table - but it is a table already found in the Hero system and used for velocity-based DCV and Range Mods as well as the uses I put it to.

It drastically reduces the maximum damage produced by speedsters and vehicle impact, as well as reducing falling damage. While this makes falls and vehicle impacts less deadly - this is consistant with the lethality assigned to guns, knives, etc. If you want a more deadly game, either reduce the BODY which humans have or (equivalently) increase the xBODY multiple on the Hit Location chart.

Some of what it does is the following:

1. Movement is now bought in terms of inches per turn, which is then split up between the characters phases. For example, 20'' per turn Flight at SPD 5 translates to 4'' per phase.
2. Move-through and Move-by damage is now based on what I call Velocity Factor' (abbreviated VLF) which is equal to the {\bf Optional Velocity-based DCV} found in the basic rules. This is on a logarithmic scale - so while a charging person still adds somewhat to his velocity based damage, the damage scale is consistant with damages for guns, STR, etc.
3. Falling damage is the same as an uncontrolled Move-through on the ground at that speed. Falling, collisions, and thrown objects all use the same mechanics.
4. Throwing distances are rescaled - so the damage of a thrown object is consistant with a move-through by an object moving at that velocity. Throwing distances have also been rescaled onto a logarithmic scale.

## MECHANICS

### 1) Movement

Movement powers are now bought in terms of inches per turn, rather than inches per phase. In order to figure out the number of inches per phase, simply divide by your SPD stat. So under your powers, you might write:
    30pts     Flight: 60"/turn

Say your SPD is 5. This means you can move (60/5) = 12'' each phase. Thus you write in your Movement allowance box:
    Flight 12"/ph

This distinction is now neccessary because your velocity in (''/turn) is used for your Move-Through/Move-By damage as well as velocity-based DCV.

SPD is now largely a mental characteristic, which represents how quickly you can think and coordinate your actions - particularly in combat. A person with a 1 SPD might run just as quickly as someone else, but he is so flustered and confused during combat that he decides on a new action only once every 12 seconds.

### 2) Characteristic Maxima

Running and Swimming now have different starting and maximum values, of course, as follows:
Running:       Base 12''/turn;  Maximum 24''/turn
Swimming:      Base  4''/turn;  Maximum 8''/turn


### 3) Powers and Point Costs

The costs of movement powers are as follows: Flight:               1pt for 2''/turn of Flight, x2 NC Mult for +5pts
Gliding:             1pt for 4''/turn of Gliding, x2 NC Mult for +5pts
Running:             1pt for 2''/turn of Running, x2 NC Mult for +5pts
Superleap:         Unchanged
Swimming:           1pt for 4''/turn of Swimming, x2 NC Mult for +5pts
Teleport:           Unchanged

Note that this is equal to the costs before for a SPD 4 character. I don't suggest recalculating costs for old characters if you decide to adopt this system - just note their movement in (''/turn) and write it down, along with their Velocity Factor'.

### 4) Velocity Factor

Aha!'', you cry, What is this Velocity Factor thing? This is a hideously complicated system.''

Well, no, not really. I will refer to Velocity Factor' (abbreviated VLF), which is identical to DCV based on velocity, as figured by the chart on page 142 of the Hero system rulebook. I will also refer to Mass Factor' later on - this is just the STR value required to lift an object of that mass (as shown on the STR chart: p173).

Below, I reproduce the chart for Velocity Factor as well as the Range Mod chart. These can be combined for simplicity, and you might want to keep the combined chart handy:

 Range (in inches)  or Velocity (in inches/turn) VLF RMod 1'' - 4'' 0 0 5'' - 6'' 0 1 7'' - 8'' 0 2 9'' - 12'' 1* (Normal Run) 3 13'' - 16'' 1* 4 17'' - 24'' 1 (Max Run) 5 25'' - 32'' 2 6 ... - 48'' 3 7 - 64'' 4 8 (Football field) - 96'' 5 9 - 128'' 6 (50MPH) 10 - 192'' 7 11 - 250'' 8 12 - 375'' 9 (100 MPH) 13 - 500'' 10 14 - 750'' 11 (200 MPH) 15 - 1000'' 12 16 (1 mile) - 1500'' 13 17 - 2000'' 14 (Mach 1) 18 ...

Note that this is interpolated somewhat from the chart on p142 with respect to Velocity Factors (allowing even numbered VLF's).

### 5) Combat Maneuvers

Maneuver OCV DCV Damage
Move-By -2 -2 (STR/2) + (VLF)d6
Move-Through -(VLF) -3 (STR or MASS) + (VLF)d6
Combat Throw - - (STR)
Non-Combat Throw Zero - (STR)
Move-By
Move-By is handled just as before; the only change is the added damage is based on VLF rather than (Velocity/5).

Move-Through
Move-Through is somewhat changed. Move-through can represent any sort of impact now: from a football player charging to a shotput slamming into a wall. If the attacker is moving under his own power (i.e. running, flight) then he has the option of using his STR or his Mass Factor (the STR needed to lift him) in order to determine his damage. He will take half this damage if he does Knockback, or the full amount if he does no Knockback.

Example: An animated statue is charging at someone. The statue has 5 levels of Density Increase, but only 20 STR. It will use its 'Mass Factor' of 35 in order to get a base damage of 7d6+(VLF)d6.

Uncontrolled Move-Through
If the attacker is moving not under his own power (i.e. he was thrown, is falling, gliding, etc.) then he must use his Mass Factor rather than his STR to determine damage. This is used to determine the damage from a runaway train, for example.

Note that a powered vehicle can use the greater of its STR or MASS, as long it is driven into the victim. A car which is sliding out of control, on the other hand, uses only its MASS to determine damage.

Furthermore, if the attacker is a living being, and is not in control of his movement, then the damage which he takes from the Move-through is doubled. That is, if he does knockback to his target, he takes the full amount of damage he did. If he fails to do knockback to his target, he takes twice as much damage as he did to it. This is because he was braced badly for the impact.

A successful Breakfall roll (with GM determined penalties) halves this damage - thus making it as usual for a Move-Through.

### Falling Damage

Falling damage is identical to an uncontrolled Move-Through on the ground. Since presumably the target does no knockback to the Earth, he takes damage of MASS+VLF, doubled unless he successfully makes his Breakfall roll (remember that there is a penalty for distance fallen).

Example: A normal person is falling at terminal velocity $$30'' x 12 = 360''/turn$$. This is VLF 9. His MASS is 10, since it takes 10STR to lift him. Thus he takes 2d6 for his mass, +9d6 for velocity (11d6 total), which is doubled to 22d6 unless he makes his Breakfall roll (which is vitually impossible given the penalty for distance fallen).

### Throwing

I have also decided to use my tables for throwing distances. From your STR you can quickly get the Velocity Factor with which you can throw an object, which is then translated into a range.

The speed and range of a throw is figured out in terms of how much your STR is greater than the Mass Factor of the thrown object. This amount, divided by 5, is the VLF of the velocity with which you throw the object. Of course, this neglects the unwieldiness of throwing the object and air resistance for unaerodynamic objects (\ie a blanket). The GM should feel free to impose penalties to the VLF as well as penalties to the thrower's Range Mod for unbalanced/unaerodynamic objects.

        Thrown Object: VLF = (STR-MASS) / 5

However, there is a maximum VLF with which you can throw an object, since you can only move your hand with a certain speed. This maximum is equal to your base CV (= DEX/3).

        Thrown Object: Max VLF = DEX/3

Example: A football player of STR 20 throws a football (MASS = -25). This would mean that he could throw is (45/5 = 9 ) at VLF 9. However, his DEX is only 17, so he can throw it at most (17/3 = 6) at VLF 6 (= 50 MPH).

Now to determine range, I must distinguish between a combat throw and a non-combat throw.

Combat Throw
A combat throw goes directly at its target, and it hits same phase as it was thrown, at full OCV plus range mods. The range of the throw I give in terms of the appropriate Range Mod. To find the actual distance, look on the chart.

            Combat Throw Range:  Max RMod = VLF - 3

In order to even attempt a Combat Throw, your STR must be 15 more than neccessary to lift it. (In other words, you must be able to throw the object at VLF 3.) If not, then you are limited to a non-combat throw.

Note that the damage done by a thrown object is equal to the STR damage of the thrower. However, the damage of the object is limited by its (DEF + BODY) and by the maximum VLF of the thrower.

Non-Combat Throw
A non-combat throw is a longer throw which is lobbed. It takes one or more segments to reach its target, and unless the target is non-moving, it will strike at OCV 0. However, you can aim at non-moving targets with full OCV (plus range mods).

            Non-combat Throw Range: Max RMod = (2xVLF) - 6

A NC throw may take several segments to reach its target. You can look up the velocity at which it moves, using its VLF on the chart.

Example: The football player from before throws the football at VLF 6. This means that he can make a combat throw out to ( 6-3 = 3 ) is RMod 3 => 12''; to bounce it off an opponents helmet, for example. However, he chooses to throw it down the field, aiming at the hex where he hopes the receiver will be. The distance he can reach ( (2x6)-6 = 6 ) is RMod 6 => 32''. This is 64m, which is close to the length of a football field, interestingly enough.

The ball is travelling at approx 128'' per turn, which is 10'' per segment, or 50 MPH.

## DESIGN NOTES

It is largely concerned with patting my own back, and saying why the system works the way it does.

Being a Champions player - my main motivation in starting this was reducing the abusive potential of Move-throughs. Being a physicist, I tried to make the system as consistantly realistic as possible. All the numbers in the system are based on Newtonian physics. It is my assertion that damage in Champions is on a logarithmic scale, where Kinetic Energy is roughly proportional to damage. +1 DC represents doubling the kinetic energy of the attack.

Note that my system reflects the 1/2 m v^2 relation of Newtonian physics: doubling velocity on the chart gives +2 DC (corresponding to 4 times as much energy), while doubling the Mass gives only +1 DC on the STR chart. This idea works well with the damages assigned to various guns: a friend and I once went through Janes's and compared kinetic energy of bullets to damage in the Hero system. We found:

      64J ->  1DC
128J ->  2DC   etc.


This works to a very good degree of accuracy, actually.

My system can calculate the Move-Through damage of a 20-gram object moving at Mach 1. The result is close, but less than this by 1 or 2 damage classes. However, damage generally goes up when there is a sharp point to an impact -- note how thrown knife does approx +1 DC more than base throwing damage. Thus, the result is remarkably consistent.

The throwing distances are similarly physical: given the initial speed of a thrown object, it is easy to calculate the maximum distance it can be thrown (in a normal gravity field on a flat surface). When solved, this gives: d = v^2 / (9.8 m/s^2) , with v = velocity.

However, as the maximum combat throw, I approximated the greatest distance which an object will travel in one second - since in order to have a reasonable OCV, the object has to hit its target on the same segment. The split between `combat' throws and non-combat throws is, of course, rather artificial - but I think it works well enough.

John H. Kim <jhkim-at-darkshire-dot-net>