"Our holdings extend for several dozen miles, until the edge of the mountains. Our realm is a secluded valley basin surrounded on all sides by mountains. The only major entrance to our knowledge is the entrance you used. That is mostly how we were able to stay undetected for so many centuries."
After a slew of different counterspells and tallying up of results, Alvius says to him "It appears you type is new to us, but bears some similarities to the magic used by a civilization we met 2,000 years ago, but they have died out by now. Now that you have helped us, we shall now reciprocate. What boons do you wish to be bestowed upon you. We will give you anything we know, save for the technique to lower the city's ward, as that could only be used to harm us."
Camilla steps back in to respond. "we have our ways. Magical abilities, spies implanted in the major nations of Europe and the Middle East. Take your pick."
(Camilla is going to be very diplomatic and intrigue focused while Heinrich is more of a warlike yet learned character.)
"Ah, I see, I can teach you this, however note that I have had 4,000 years to hone my ability, so you will likely only be able to summon a handful at a time. Regardless, the first step is to ingest a powder made from the ground bones of a Windfolk, all long dead by now to a horrible plague, but I still have some in storage." He walks off into a large closet filled with vials bearing faded labels, and returns with a clear jar full of a crystalline powder, handing it to him along with a small cup. "get enough to fill the cup, but no more, as you will be afflicted with the same plague as the Windfolk, and it will cause great suffering even for someone such as you."
Heinrich eyes the jar for a moment for following the warning, only getting enough to fill the cup. He hesitates for a moment for ingesting the powder as directed. He seems to be fine for a few seconds before he gets dizzy and then doubles over in pain before vomiting what seems to be pure blood much like the spinal fluid collected earlier. Once he was finished, he stands up and tries to clean himself off to the best of his ability, though he seems visibly more sluggish than he was before. "Blegh, that was horrible... apologies for the mess."
"That is fine, these floors are made to resist all sorts of noxious materials. Now, for the mental part. It is quite easy to summon a single Apparition, simply imagine yourself doing something with intent, and an apparition shall do it. The hard part comes in when you have to split your mind into several pieces to control multiple of them, and more importantly, recombine the shards afterwards. I suggest you start with just one, and progress cautiously, unless being brain dead or insane is an attractive prospect to you. Go ahead and try summoning one, so I can judge your natural aptitude however."
Heinrich chuckles at that. "No, that is not the most interesting prospect I've heard." And with that, he stands for a moment and imagines himself picking up one of the random jars in the room. After several seconds of focusing on that image, a single apparition appears doing that exact thing.
"We will simply teleport you to your destination, we would not be so cruel. Before I return you however, I tell you that I hope that you persist as we have, and are not consumed by the gaping maw of the future." Heinrich sees a flash, and then is back exactly where he was before he left, without so much a a little jostling from the trip.
(end it here?)