Per 
The guest speaker stood before a few fresh faces, one anomalous individual who the Foundation was turning a blind eye to due to his prowess in the field, and a bunch of researchers. He was in a white tent in a desert, which would be promptly incinerated after he finished the talk, to erase all evidence of the individuals that had been there.
"Hello, everybody!" The guest speaker boomed, in a gruff voice. "I am Sir Solomon, Knight of the Organisation For The Collection Of Anomalous Knowledge. For those of you who don't know, the OFTCOAK-" He says it 'Oft-Coke' "-are freelancers, individuals who have proven resistant or impermeable to amnestics, and who the Foundation have allied with before, though the occasions are usually expunged from history. The OFTCOAK collect information on the anomalous." The 'Knight' straightens his tie, clears his throat, and continues.
"I am a guest speaker here today because I am the world's leading expert on immortality. All of you here today know about a few immortal SCPs. SCP-106, that one's immortal. At least, of a sort. The Broken God is immortal. Kinda, anyway, because it can never truly die. The concept is immortal, and the followers will resurrect it. Actually, we're not so clear on that one. SCP-SCP-J… Well, I get that it's a joke one, but it does exist in some locker somewhere. It's immortal in the minds of those who view it. I met it once, but then I had to go home because my wife said that if I wasn't back by 10, she'd leave me and go have sex with some other man. But, uh, enough of that." Solomon clears his throat again.
"There are a few kinds of immortality, if you believe that the soul is eternal, as proven by whichever SCP is a phone that connects to some lady in the afterlife. Anyway, the four kinds are as follows."
"The first kind is impermeable immortality, otherwise known as Type-I Immortality. The second is immortality via regeneration, usually shortened to IBR, or referred to as Type-II Immortality."
A pause.
"Sometimes, they call it auto-regeneration. An example of that would be SCP-2416. The third kind is Type-II-A Immortality, where you are regeneratively immortal because of the effect or effects of other entities. It's usually used by low-level-reality-bender farmers who want lots of chicken wings or burgers but only have a few animals in the field. Some serial torturers use it to maximise the amount of torture they can inflict on a victim. The third- Sorry, um, the fourth type is Type-III Immortality, in which the immortal is so because they work in spite of being broken. SCP-418 is an example of that."
The guest speaker straightens his tie once more, a nervous tic that remains from the days when he got nervous still. Before the amnestics took away fear and hate, before the amnestics damaged his emotional capability. At least nothing else was damaged. "And, um, that's all the types of immortality. Apart from the body-stealing immortality that Doctor Bright has. And SCP-1510. That's Type IV Immortality. And, by the way, the correct way to write that down is with Roman numerals. So 'V' and then 'I'- No, 'I' and then 'V' for Type IV, three 'I's" -He says it like 'eyes'- "for Type III, so on and so forth. There's also the hotly debated Type V, but that's not technically considered a type of immortality by most people. It's basically where you can regenerate after you die, but you can be killed permanently. Like SCP-1007, or SCP-682. Hypothetically."
Someone in the audience shouts out a question. "Why isn't SCP-682 auto-regenerative?"
He loses focus for a second, but a repeat of the question brings him back to reality.
"Why is 682 not auto-regenerative?"
"It's obvious, you moron. Because we have no idea if we've ever actually killed it, or if it just looked like we did. Even that time that we ran a diamond-cutting laser over it and split it in two, for all we know it just split into two creatures with one mind."
Then, suddenly, a gunshot rings out from a Foundation researcher, a fairly high-ranking one who decided that it wouldn't be good for this individual to keep running around with all his knowledge of the anomalous. People run, panic, scream that it'll be them next. They're just researchers, not experienced soldiers. Apart from that guy who has experience in the field and who the Foundation are turning a blind eye to. Deltern Solomon puts a hand to his chest, where a crimson stain blooms. The bullet's force drives him backwards, and he hits one of the supports keeping the wall up.
Help! Somebody, help me! Deltern Solomon thinks, before remembering what he brought with him. It doesn't numb the pain, it doesn't numb the fear that it won't work, but it still comforts him a little.
The bloody rose spreads further on the guest speaker's best shirt, and, unconscious from blood loss, Deltern Solomon collapses. Lacking oxygen from all the blood in his lungs, and being prevented from breathing by all the blood in his throat, the guest speaker dies, and falls on his face in a graceless way, his hindquarters up in the air. And, as suddenly as the shot rang out, the guest speaker hops upright again.
"Ha, you bastard! You thought I'd talk about immortality without bringing my own Immortality Stone?" Sir Solomon says. "I'm as paranoid as any other human being hunted by pataphysical entities capable of transferring themselves through any human media capable of displaying a description or image of them! You'll never kill me!" The guest speaker runs out of the tent, letting his wild, tangled hair and beard be caressed by the wind, letting the reek of fear pour off him. Praying that the Foundation values the people here more than the anomalous object he now possesses- hoping that the knowledge in their minds is worth more to those callous murderers than an anomaly that makes people immortal. He makes a beeline for the teleportation tent, somehow sweating even though he's been running for no more than ten seconds. He gets in. He takes a brief moment to catch his breath and admire the shining metal around him, before slamming the door and speaking the name of the location he wants to be in.
Somewhere in an undisclosed location, a man with blood on a now-ruined, previously high-quality shirt, appears in a toilet that was shut down about five years before the warehouse it's in. He smooths his hair, making sure to use some still-remaining toilet paper to wipe the sweat off his face.
A few minutes later, he gets home and finds his wife, Mycelna. His wife who he went to the trouble of stealing an item capable of opening tears in reality to other dimensions for, after she was kidnapped by a universe-hopping creature, his wife who is from an alternate reality, on the couch, making out with some random guy who looks about half her age.
Well, you can't win them all.
