The guards look fine! To all appearances they are keeping a perfectly normal watch! They do look alarmed when they notice him leaving the tent, which they do nearly immediately; their stances shift from 'on guard' to 'preparing for a fight to start within the next couple moments.'

"—Knight-Commander? Is something wrong?"

"Shrugged something off. Didn't spot a scry or anyone coming in."

That's really concerning!!!

One of them has a touch of sorcery and was chosen for guard duty on that basis; he pops a Detect Magic and focuses on Blai for a couple moments. "—That's a Conjuration aura stuck to you, sir."

"Stuck to me? - does that imply that in addition to whatever I saved against it landed or would an attempt alone leave that -"

"It's very faint, it doesn't look to me like it landed."

He can't wake Nenio, it's the middle of the night. He needs to be more up on what there is to know about Crusade-ly threats without her at his elbow all the time. "Possibly someone was trying to abduct me, is there more in the tent to suggest they got away themselves -"

Detect Evil? Detect Magic? Throwing sand around the room to check for invisible people?

They eventually report that they cannot find any lingering auras in the tent. ...Including the auras of any teleportation spells.

"...if they didn't teleport out and they aren't still there is there any chance they got past you? I didn't see anything but wasn't facing the entrance."

"Maybe if they were... incorporeal? And under an Undetectable Alignment?"

"...can't rule that out." If he were not instantly in the habit of sleeping in his Cloak of Resistance as soon as he got it he'd certainly start. "Any other guesses?"

"It could be the sort of spell that can be cast over a long distance even if you don't know where the person is? Like Scrying, except that's divination."

"...I don't think I could have thrown off a Wish, even if one used for transport would leave solely a Conjuration aura..."

Nod. "And all the other spells I know of to grab people are designed for outsiders." This guy is pretty sure the rumors that the Knight-Commander is an angel are false.

 "I heard if you sleep in a Bag of Holding no one can land spells on you."

"...you'd suffocate."

"And someone could enter the Bag of Holding under much the same conditions they could enter the tent."

 "You could make sure it was so full that no one could fit? I dunno if that would work if they were incorporeal, though."

"—What you'd really want is a Rope Trick, do any of your wizards have it?"

 "Wouldn't that have the same problem?"

"What I heard is that you can only fit eight people even if they're all gnomes or animals or something. Wouldn't do much against a Wish, but I don't know of many things that would."

"Well. If we have no avenue for tracking down what just happened - I do still need to sleep tonight."

"I could try to keep up my Detect Magic? But by the time we saw the magic it might be too late, depends what it was."

 "We could wake all the sleeping clerics, see if anyone has anything that would help."

"I do not think we should wake all the sleeping clerics. If I should vanish in the night Ser Tirabade has the command."

If he vanishes in the night the Crusade has lost. "Understood, sir."

Well, he might retrievably vanish in the night. "Good watch." And in he goes.

He does not detect any other spells cast on him during the night!

Great! He's awake a couple hours later. Anything come up during those couple hours?

Not urgently! His guards would like to know if they should convey messages to his wizards or anyone else about their spell prep for the day.

No specific instructions, it's really too late to track down whoever tried whatever, but he'd like to see Nenio as soon as she's out of her book.

Here she is!