Can you name this invisible beast?!
 

Invisible - but not detectible to telepathy

You shock something. <3x>
You shock something. It was a great hit!
You shock something.
You shock something. It was a great hit!
You shock something. <5x>
You have killed it.

You double moved it as you have 6 hits a round.
Its armor rating clearly isn't that great, because you didn't miss.

But it has a fair number of HP, because you do 112 points per blow against creatures not resistant to lightning

My speed is +18 if that makes a difference.

Possibly a midlevel Q?
Edit: If you enabled verbose messages, it would "squlch" and "quiver in pain", and you'd know for sure. The other possibility is will'o'wisp, but you are unlikely to just run into one like that.

Yes Q is the prime suspect. Will o wisp is electricity resistant (or should be).

My guess would be a lurker

I was thinking that too, or trapper.

Trapper was my first thought, too. But that beast survived 11 hits for ~112 damage, so it must have twice the hit ponts.

99,9% certain lurker. You need to have more dmg/turn to two-shot a midgame Q or a trapper.

I doubt Lurker, too few hp. My monster viewer is a hack so cant say for 100% but I'd say it is a Q.
Using this: https://thraalbee.azurewebsites.net/monview/
And this in the filter field:
results in three Q's, all native to dl 71.

Right now only the "Plot" option works, the "Tabulate" is broken (EDIT: fixed)

More evidence: lurkers, and more so trappers, have decent AC, whereas Qs have almost none. So 12 blows in a row connecting favors a Q.

Aren't Q's detectable by infravision?

@grotug--
The OP did not mention infravision.

I think it's very rare for a developed character to not have infravision (only two races don't have it natively).

It sounds like, along with the Competition, we need a regular Angband Puzzle. A few lines of text from the game, and the community has to figure out what was going on.

Human Warrior with literally no infra

All resists including blindness, fear confusion, hold life. No stun though and I swap ESP and See-Invis

My first thought also was a decent sized Q. you didn't miss once in 12 shots and it took >1000 damage.

And speaking of Q, I have a suggestion for most annoying creature that doesn't add difficulty but clearly detracts from game play experience:

NEXUS Q. I suggest nerf or remove the annoying ability: TO

my current char trying to do stat gain walked into a room 10 times in a row only to get insta-TO to other side of dungeon. I cant even walk into the room to light it up and target the f*cker. This is just irritating AF.

That's what ball spells, or stone to mud for LOS are for . Or juat go somewhere else. What is special about the room?

LOL I have OCD about finishing levels if the loot feeling is >6 Paladins be ball-spell challenged. I fight wiruin by getting faster than him and with sound/stun resistance, and single combat

:-)

[Finally got fed up and aimed a random wand of acid balls in there and "scream of agony" and the room had an Elvenkind armor sitting right there I needed haha! dunno what the ability is yet...]

Imo Teleport other should be a resistance that the player and enemies can have. The curse is too difficult to get and too dangerous.

Playing a Mage with dimension door is kinda fun though as when they do that you can just teleport straight back.

Edit: Just playing at the moment and found a room with 6 different Qs in including his highness. I think I'll just go find a different room ]:<