Venom lasts 216 seconds in nightmare, and does a total of 86 HP damage over that 216 seconds. The negative regen is ~0.4 per second, which is less than max life regen of most characters with max endurance. Recruit is 57 damage over 144 seconds, Veteran is 72 damage over 180 seconds. Energy transfer is separate from venom, and is a flat -0.5 per second, and gives 0.1 or 0.2 energy per second, depending on level. If you want to heal regular venom damage, it costs a total of 0.45 * 86 = 38 energy to heal that damage. Antivenom costs 15 energy, or healing costs 38 energy. Including the 10 HP from antivenom, Heal beam level 3 requires 43.2 energy and 13 seconds to heal 96 damage. Surgical laser level 3 requires 40 energy and 8 seconds to heal 80 damage. If you have more than one stack of venom, it is significantly more energy efficient to cure the venom than to use heal beam level 3 to keep the person alive. Heal beam level 3 can keep someone with 17 stacks of venom from losing any life. If you are severely hurting for energy, then leaving someone who is losing a small amount of life or still gaining life. Note that each stack of venom hurts your overall walking speed and make you more susceptible to getting hit again. Most characters will survive 4 stacks of venom, but it will take them a very long time to fully regain that health back. If you are planning on using heal beam to accelerate that process, it would have been more efficient to prevent that damage in the first place with antivenom. Unless you know for a fact that someone only has 1 stack of venom, it's much more efficient to remove that stack of damage. Endurance adds 0.043 HP regen per stack, 0.387 HP regen at 9 stacks. This is enough to make even the lowest regen characters (engineer and commando at 0.121) still gain life with 1 venom stack. I don't know who started this war against using antivenom, but it's time to stop. If you are medic, please do the efficient thing and cure the venom when people are losing HP from venom, unless you are really low on energy, in which case you should heal venom that loses HP of over 1/3 seconds (unless you have supply station). Additionally, I believe that heal beam and surgical are relatively poor choices to heal players. Surgical has 0.5 energy/HP, and heal beam has 0.45 energy/hp. In terms of utility, surgical wins every time, except when healing less than 40 HP. For comparison, Nano weave heals 0.21 energy/hp, and restore is 0.42 energy/hp on a single target except when healing less than 70 HP, and the amount is drastically reduced when multiple targets are involved, especially considering the bonus energy and self heal. Antivenom, when curing venom, heals at 0.15 energy/hp over the full 216 seconds.