Sure. But you are looking for a secluded area very close to the lizardfolk village, yet where lizardfolk are unlikely to wander by.
At least for a minute or so as the lizardfolk imprisons himself, then the wizard abducts him somehow.
A swarm of gnats parting neatly around an unseen object. Low hanging leaves, vines and branches moving out of the way as an invisible wizard passes through. I think you're pretty safe if you're floating in the air, though, especially as you're pretty quiet when your life force is elsewhere. My bigger concern would be something with a decent sense of smell (not Scent necessarily, but more typical of predator animals than that pathetic human olfactory sense) that can fly.
I believe prestidigitation could change the wizard's smell.
Thinking on it, Magic Jar forces the target to make a Will save to avoid an undesirable effect. Is that an "attack"? "an attack includes any spell targeting a foe or whose area or effect includes a foe" - it seems like you are targeting a Lizardfolk with the intent of imprisoning him. I'd call that an attack.
If you are referring to the fact that Invisibility ends if you attack someone, I would counter with the fact that the Wizard's soul is in the Magic Jar, and his body is reduced to comatose status. The Wizard is not attack from/in his invisible body, so the Invisibility spell would not know of the Wizard's actions in the Magic Jar
20 minutes sounds like plenty of time until 20 minutes turns out not to be enough time because complications arise. There are seldom any guarantees. I can see a GM deciding "no problem, you capture the Lizard", or I can see complications arising. Another lizard starts interacting with yours - can you bluff your way around a chat with a buddy (or mate)? That lizard was supposed to get back to guard duty after he Drained the Gecko where the heck is he?
"Gonna take a dump."
Sure. At the same time, whispering (not speaking in a strong clear voice) is DC 15, where “People talking” is DC 0. An unarmored person trying to move quietly (so someone attempting stealth with Take 10, no bonus or penalty) is a DC 10. I say you are harder to hear than people talking (as you are one person briefly speaking), but not as hard to hear as someone being as quiet as they can while slowly moving.
Let's say DC 5?
Becomes DC 10 if I am 50 feet away, DC 15 if I am a hundred feet away, etc based on how scaling works.
If the lizardfolk do not have class levels, they're stuck with a +0 listen modifier.
Where does it say you can order the Steed to carry freight (such as an unconscious or gagged and bound humanoid) rather than a rider? For that matter, if the mount is created for a specific person, who can then ride it, who is in charge when that one person IS riding it. The mount’s communication skills aren’t really set out in the spell description, but “better than horse” seems a major assumption.
That is a good question, but the big D in the spell duration line indicates that the spellcaster can dismiss the spell, so the Wizard evidently retains, at the minimum, enough control over the Phantom Steed to dismiss it.
That’s also 10 minutes’ casting time 20 if you also want a steed) within a few hundred feet of the village (since you are still within Magic Jar range) speaking in a strong, clear voice all the way. Another risk.
Not if we're assuming the Polymorphed Wizard carried the lizardfolk away for a bit.
I think you are projecting your game style on everyone here. My players don’t take the attitude that, as they can probably kill the townsfolk, it is OK to bully them. In fact, they would more likely be the ones the town hires to deal with such marauding bandits and brigands.
In which case, the innkeeper should have no issue contributing to the success of the mission the town hired the PCs for.
Most adventures place characters in situations where combat is inevitable. However, xp is awarded for “overcoming an encounter”. Talking down a belligerent father or brother who thinks you are taking advantage of his beloved, innocent daughter/sister is just as much “overcoming the encounter” as chopping his head off (and leads to less ill will with the townsfolk, at least in most cases). Story awards are also suggested. That’s the Pathfinder SRD - I think WoTC kept xp out of theirs.
I agree that XP can be gained from non-combat encounters, but do you gain as much?
Emphasis added. Not “while possessing another creature”, while in the jar itself. While you are out being a LizardFolk, your body just lies there and, unless you can perceive it as a LizardFolk, you don’t know what, if anything, is going on around it.
Given that the time spent possessing the lizardfolk will be a few minutes, ideally, I would hope nothing pops up just as the possession is occurring.
To the gnat issue, you don’t have to possess the whole swarm. You can only sense relative power, with a minimum 4 HD differential to perceive any two as different. Having the Imp nearby probably helps by setting at least one baseline. Mind you, “gnat” and “standard lizardfolk” are within 4 HD of one another. I’m inclined to think nonsentients like vermin don’t count, though, as the alternative would render the spell pretty much impossible to make beneficial use of.
I wouldn't worry about it. I was just responding to Nezkrul's sarcasm with my own. Gnats are not a threat, except to vegetation.
Reasonable interpretation suggests you don’t pick at random between everything within your radius. Although technically nothing says you get info on distance to each target, much less how close together the targets are, practically there is reference to “a group of life forces. Hopefully, the thing you want to possess is 4+ HD different from your imp so you don’t accidentally possess him and have to start the process over. [He’s likely got the second best will save in the swamp, hasn’t he?]
Magic Jar lasts for hours, so a bit of trial and error isn't totally out of the question.
Can the wizard use magic to locate the dragon's lair? Almost certainly. If it could also have been done by a simple Gather Info roll and a couple days slog through the swamp, is it a big deal?
Well, as you yourself mentioned, timing may be of the essence.
