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Join Date: Mar 2004
Old 03-04-2009 , 03:14   [L4D] Health Bonus Update Fix
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L4D Health Bonus Update Fix 0.1.2

This plugin will fix the health bonus not updating after healing someone. Basically if A heals B, then the health bonus for A will update, but the health bonus for B will not update till someone shoots him.

Boost the Health Bonus Legitimately
There is one legitimate way to "bump" up the health bonus, basically if you have 80hp and a medkit and another person has 10hp and no health pack, then you would heal the person with 10hp. In this case it is no longer necessary to shoot the other person to get the health pack bonus to update.

Note: Originally this fixed a health bonus exploit due to pill passing or healing, but the purely exploitative part was patched by Valve in a March 11, 2009 patch.

In other words health bonuses will always update when someone is healed or pills are passed around.

This plugin will block the exploits related to the health bonus in Versus mode.

Exploit Description:
1) Passing pills around before closing the safe room door
2) Healing others with low health and then shooting them

In situation #1 the game thinks everyone has pills.
In situation #2 the game thinks the healer still has a medkit so it's the same thing as getting 2+ extra medkits at the end of a level.

Why Use The Exploit?
In both situations it is possible for the health bonus to go from 120 something to 180 and thus you get easily 60x4=240 more points (and that's just for map1), easily up to 1500 extra points overall on the campaign just from health bonus glitching.

I look forward to people picking this up until VALVe fixes it in their own patch, since currently teams glitching the health bonus virtually eliminates any point difference one might've had otherwise.

How Is The Exploit Blocked?
Whenever pills are passed to another player or someone is healed, the health bonus update algorithm gets run. We force L4D to update the health bonus for the affected players by giving them +1 temporary health (if they hadn't any temporary hp already), which almost immediately drains down to 0 temporary health.

Thanks to:
Fission for helping me test this throughout the entire lifespan and helping me figure out how to reproduce the two health bonus exploits.

Trinity Gaming for doing a "live" 4 survivors test without using cheats or any SM commands.

ShadoMagi for inspiring me on using the side-effects of m_healthBuffer to update the health bonus.

  • 0.1.2 - Changed version cvar to l4d_eb_health_bonus (it was too long), and removed all compilation warnings
  • 0.1.1 - The health bonus will update 0.1 seconds faster than in v0.1
  • 0.1 - Initial release
Attached Files
File Type: sp Get Plugin or Get Source (l4d_exploit_health_bonus_block.sp - 2235 views - 9.5 KB)

Last edited by Downtown1; 03-14-2009 at 04:52.
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