MyNeighbourTrololo said:

The investigator is sent to St. Mary's Hospital or Arkham Asylum as normal. The tentacle uses the same game mechanics as the Tendril of Nyogtha (from Innsmouth Horror), which is what I modeled the Tentacle of Zoth-Ommog after.

I can guess it. The point is sheet doesn't states it. It states what happens if tentacles is defeated or evaded, but doesn't states what happens if defeats. 

 Something I came up with:

The "Upon the Cliffs" and "beneath the Waves" abilities are probably a bit too harsh. On the other hand I was thinking of giving Scylla Magical Resistance and Charybdis Physical Resistance, but I thought it might be too much.Thoughts?

I hate Rhan-Tegoth.  I like the story and the creature, but the in game Ancient One is just a chore, Worshipped by ONE monster from a different expansion, and has a short doom track that occassionally, totally randomly, gains doom and there's nothing you can do about it other than cross your fingers when monsters are drawn.  It's very uninteractive and not fun to play against. 

So, I'm thinking about a revised and fun one.  Same final battle rules, but Ancient One powers are...

Horror at the Musuem: When a monster in the Uptown or Merchant District streets moves, or a monster in the sky cannot move due to no investigators being accessible, they move to the Miskatonic University streets.

Insatiable Hunger: At the beginning of the Mythos phase, return all Monsters in the Miskatonic University Streets to the cup.  Add one doom to Rhan-Tegoths track for each monster removed this way.

Worshipper abilities...

Rhan Tegoths worshippers bring sacrifices to their master, and yearn to be sacrificed themselves.  Whenever a Monster Surge occurs, place an additional Monster at the Admininstration building.  When a cultist is placed on the board, place it in the Administration building instead of its original location.

Note, that as they get eaten at the start of the Mythos phase, the investigators have a turn to kill anything that's wound up there.

I decided to do some revisions to two Ancient Ones that I had posted earlier: Cyaegha and Polypous Magnus.

His Start of Battle ability comes from the fact that Flying Polyps can render themselves invisible.

Cyaegha's attack has changed, and now has a Start of Battle abiity that modifies her Combat Rating based on how many Nagaae and Cultists are in Arkham when she awakens. Speaking of the Nagaae, here is the new Nagaae monster marker:

At most you will need 8, since a maximum of 8 gates can be open in a one or two player game before the Ancient One awakens.

 These look truly amazing!!!!….I'm to the community….I was wondering if anyone had ideas for "Classic Killer" Great Ones (Jason, Michael Myers, etc)? 

Too hard? Too easy? Any feedback appreciated. Particularly if anything can think up a more interesting final battle ability.

Don't worry about what a Yugg is, it's a monster I'm gonna make.

Looks very interesting!  48 clues in the game, thirty to seal six gates…  Which leaves 18 to play with for not getting killed and dealing with Elder Signs, will make the game very tense and really limit your ability to blow clues on things.

The only problem I could see is that if you *do* run out the game might become a bit stagnant - say we have eight clues left and one gate to seal, and we get a burst.  We *know* we can't possible win by sealing now (bar a flukey Elder Sign draw), so we just have to wait for the GOO to awaken, which might take quite a few turns of relative boredom, but it's a minor criticism, and I guess we could probably use the time to gear up.

For the combat ability, how about just upping the stakes.  Each investigator must make a Fight (+2) check, with the modifier decreasing by 1 every turn.  If they fail, they are devoured.

Adelphophage said:

Don't forget you can score a closing gates victory! And sure, a gate burst can be a problem, but this could force the investigators to find a better strategy during the game (no gate bursts at certain locations, hence more focus on low freq ones and more monster surges). It's interesting.

I'd go with a shorter doom track. 12 seems fair to me, or even 11, if you want to rush the things a little. But good ideas :-)

Alright, here's one I came up with. I'll admit that I came up with the abilities of this Ancient One first, then came up with an identity to go with it. I used Ossadagowah because barely anything is known about him beyond where he lives, his heritage, his appearance, and the fact that he's called "The Sky Devil."

Technically, it's an AO transforming Flyers in Fast Flyers, but has no other impact on the game. Maybe you should work a little on something making Flyers much more annoying? Like allowing them to enter all unstable locations and giving them two extra toughness?

It should make Cultists into flying monsters too. Then they can appear, fly up, and land on you without warning, and they are hard to evade. (Easy to fight, of course, but fighting delays you for the turn, so they'd actually be a bit of a nuisance.)

The main game ability is phrased in a slightly confusing way. All effects take place, then special effects don't? Try this:

"When an Environment (Weather) or Environment (Mystic) Mythos card is drawn, resolve the gate opening, monsters, movement and Clue token as normal, then put the card on this sheet without its special effects taking place."

The picture's a bit generic too - and upside-down of course. For something a bit more unusual, try taking a crop of this: http://attachments.conceptart.org/forums/attachment.php?attachmentid=1132564&stc=1&d=1293754005

 That picture is awesome and you should feel awesome.

Thank you. This is precisely the sort of advice and assistance I need.

I rephrased the ability like you said. I also changed it so that Cultists are Flying -- though I'm considering have it be Formless Spawn that get Flying (SInce he's Tsathoggua's son). Or maybe both?

While were at it, here's another one I'm not entirely happy with. There's too much text for my taste, and it feels a bit… hodge-podge. Or maybe the word I'm looking for is "busy," or "muddled." something like that.

Has anyone tried making a ZALGO ancient one? I'd imagine it's effects would involve extra sanity costs for tomes and monsters appearing in stable locations.

(In fact, someone might want to make a expansio based on the fear mythos some time.)

I posted a few things in the custom investigators section, but I forgot I have a few Ancient One concepts that people might enjoy.

Starting with Crom Cruach.

Inspired by the creature from the animated movie "The Secret of Kells" (and also of the Pagan deity of the same name from Celtic Mythology), Crom Cruach creates a board state that functions oddly, yet in a fun way.  The most lethal thing that can happen against this Ancient One is a gate opening on the Woods, but sealing that location becomes especially prominent here as well.  Hope you and your buddies enjoy.

Next, I have Bloody Marie, from a recent pioneer project in video games: "Skullgirls"

Originally, I had tried to create a very complex "wish-granting" function to this Ancient One, but ultimately it came off a little too similarly to The Lurker at the Threshold in terms of mechanics.  Plus, I wanted there to be at least 1 other Ancient One that interacts with Mask monsters in our box of Arkham stuff.  Though I didn't include much of a wish-granting mechanic within the normal boundaries of the Ancient One, all of the sinister plots revolve around an old version of the "wishes" system.

Finally, from the popular playing card game "Magic: the Gathering", here's Lorthos the Tidemaker:

Straight from the depths, Lorthos covers Arkham in a massive flood!  This is an Ancient One designed to make a non-relevant monster type (Aquatic) suddenly VERY RELEVANT.  Understandably, making every part of Arkham aquatic is a bit game-breaking at times, but the number of interactions is fairly limited since there aren't even a surplus of aquatic monsters in the monster cup most times (I personally play with everything in the monster cup, but I don't know what other people play with).

Down below is a download link with the Strange Eons files for all 3 previewed Ancient Ones and a full set of Sinister Plot cards to compliment them.

http://www.mediafire.com/?n381emr1w1afy9y