Hi, really interesting threat and posts of you all.
I will make it easy, won't go much into details, but for me the substances giving you the sense of "someone"/a consciousness are as such:
First Salvia d., it is very common, and it can be really deep. Be prepared.
At the same stage I would place DMT.
5-meo-DMT also gave me some "contacts", but I have a weird body high. Every-one is different, and react differently.
Going down in the list, psilocybin or LSD can also induce a contact, but it is less likely to happen, and mostly if it happens it is on a high dose.
Also to note, once while on a high dose AL-LAD (it's still is one of my favourites

), don't really know the dosage, it was with a friend, who also had a dropper (we did it together), it was measured to have 100-120 ug per drop, we both had two 50ml vials.
One night, we just abused, thinking "everything is nice, go one!", putting AL-LAD in every drinks we took, the table was full of the liquid, just to say...we where above 1.5 mg for sure, maybe near 2 mg (20 drops seems not unreal we where just a bit too stupid that night), it was a hard experience for some moments (we were used to psychedelics, and enjoyed them a lot, so it was intense but also really pleasurable sometimes), and we both saw the same kind of "entities", so don't really know what to thing about what happened that night, but we were talking to kind of "spiritual entities", telling us not to reach the no-return place, that we had understood what was meaningful and just to let it go.
The strange thing is that we both saw the same kind of entities, telling us right the same thing, without speaking, you just know it.
Maybe a small visit in the madness, possible
2C-I-Nbome can produce it, I also had one time this feeling while on a pretty high dose 25C-NBOH (I wouldn't recommend).
This is for psychedelics (I could have missed one or the other, these are the substances I'm thinking about right now).
On another stage there are deliriants.
Note: Salvia d. is somewhere between a deliriant and a psychedelic in my point of view.
One time on a K-hole, didn't last long and can't really remember our conversation..
But you have DPH (and related), Scopolamine, I had a similar effect than (see)-> *.
Nothing really interesting, you are pretty sure to see people, this is right, it's almost Always the case, but there is no deepness, nothing, you are just in schizophrenia for some hours.. Also can be really weird the first times, once you know how it goes, it is ok, but I can't see why taking this anymore, but surely you will talk to friends or others who aren't there, giving them a drink, passing a joint you never rolled, but you are convinced you have...seeing animals, dark bugs sometimes, it's just a real mindfuck for nothing.
*-> While I was on a pretty high dosage Quetiapine, I decided to cold turkey, and had hallucinations, a feeling of oppression after some time, seeing and feeling "dark entities", it was pretty awful, never again (even if the visuals where nice at the beginning hahaha).
Don't really know what happened, maybe another visit in the madness ?
All good.
To conclude, Salvia d. or DMT, you are on a good choice, these are to two I would suggest to anyone wanting these kind of experience and learn something from it.