I'm wondering how DMs out there read the "affects only a target taking ongoing poison damage" like in the description of an Ancient Green Dragon's Mind Poison.
Several Dragon abilities state that they only "target" someone who is suffering from an effect (usually stunned or dazed), but this one states "affects" instead. Does this mean that the person snaps out of the Green Dragon's control the second they make the Save against the ongoing poision damage? Does it mean that the slow progression of the Mind Poison ends if the Dragon has not taken control of the character before they save vs the ongoing poison? (It takes two failed saves to have the target be unable to continue saving vs the power's effect.)
If you read it as ending the second the ongoining poison damage does, then an Ancient Green Dragon (a Lv 27 Solo Controller) would be limited to short term minions, as all of them would die from poisoning a short while later. If you read it as it as stopping if the control is not perfected before the ongoing poison damage ends, then it might be a balancing things. But if you read it as only needed to target a creature taking ongoing poison damage (but then being separate from the ongoing poison damage after that point) then the feel changes yet again.
Effectively the three situations I'm seeing are this:
1) The Ancient Green Dragon can collect minions/mind-slaves when required, but doesn't do it all that often because they always die a short while afterward anyway.
2) The Ancient Green Dragon ensures it can poison the more powerful foes first, then tries to turn them to its side. Sure, it loses some of them with too much constitution, or who die due to the original poison, but so long as it can convert some of that deadly toxin into the sort that warps minds, it will likely have a respectable army. (Unless, of course, "Remove Affliction" rituals are a common thing in your setting.) [I'd see this sort of Dragon, outside of combat, having a weaker Green Dragon, or a minion with a mild poison on their weapon, poison a captive before the Dragon uses Mind Poison, and ensuring they remain poisoned until it's clear the Mind Poison has taken effect, at which point they would be given an anti-toxin, and healing. All the better able to ensure that they won't die before they prove useful to their Master/Mistress.]
3) The Ancient Green Dragon poisons its foes and then takes over their minds. Once the process begins, it's a matter of luck, and the Dragon is actually better served if the deadly toxin passes through the system. There's no point really in having servants who are half-dead when you get them. [I see this Dragon, outside of combat, having a weaker Green Dragon (or a servant with a mild poison on their weapon) poisoning captives before it uses Mind Poison. Then force feeding the captive some kind of anti-toxin while it waits to see if the Mind Poison has taken effect. If not, then it would either continue trying once Mind Poison recharges, or wait a day if a captive was damaged too much by the original poisoning. This is the option that basically ensures that captives would fall victim to the Dragon, given enough time. Every six seconds, the Dragon has a 33.3% chance of being able to try again, and with the milder poison, it wouldn't have as much of a risk of killing captures of any respectable power level.]
I'd like to hear from DMs who have used this monster and see if they have any alternative options they came up with while reading the power. It has less of an effect on combat than plot, really (depending on how many rounds the Dragon survives before dying [or fleeing, which would then bring up the other questions, since there is no mention of a range restriction in the power's description]), but while looking through the various Chromatic Dragons, this is the only one that caused me to pause and wonder at the wording.