How do I Kill it?

[phaedrusxy]

Is there a difference between Cheater and Twice Betrayer?

Yeah. The cheater is far simpler, and something that you might actually get by a DM. At it's core, it's basically just a cleric of Mystra with the Initiate of Mystra feat (which lets it cast inside AMFs). I think Dweomerkeeper levels might have been included for Supernatural spells, but that's really just icing on the cake. The Twice-Betrayer is... a bit more elaborate.  (IIRC, I think he had both Initiate of Mystra and a bunch of the Shadow Weave stuff in the same build, with a crazy backstory to explain it)

[Endarire]

Cap, pweath explain this:

Get a few small demi-planes. Smash them into your plane reducing it from a 5 dimensional plane to a 3 dimensional plane. Watch all magic fail. Kill him with a monk.

[Captnq]

Ah.
Years and years and years ago there were books printed that actually explained the way the multiverse was put together. We're talking D&D basic here. That's always been my problem with manual of the planes and the planar handbook is that it never got into the nuts and bolts of HOW cosmology worked.

I find the D&D immortals boxed set had the best set of rules on cosmology. Basically summed up:

Take  2-d creature and do 3-D things around it. It will think you are magical.

So a 3-D universe is our world.
A 4-D universe is a world with magic.
A 5-D universe is a world with Gods.

When two universes collide they both lose a dimension for a short period of time. A 5-D down grades to a 4-D. Hit it again with another universe, it down grades again to 3-D.

And before you ask, can you hit it again to reduce it again? No. It's too thin. At 3-D it would be like trying to crush a pin with a balloon. You'd need another pin and need to hit it JUST right. Not impossible, just very unlikely, because the planes only remain compressed for a few centuries, at most.

Frankly, there are no real rules on cosmology and you'd be making it all up anyways, So I just use those rules. They are as good as any others.

[KellKheraptis]

For the record, even if he were a Cheater or Twice-Betrayer, my Red Wizard build pwns both of them   Only build within the limits of the challenge that I know of other than Pun-pun or -maybe- the Omnicifier.

As for the AMF issue if he's just a fighter?  TK a bagful of shrunken ballista bolts using violent thrust and turn him into a pin cushion.  Planar Bubble if need be to toss a demi-plane full of sharpened sticks at him until he dies, and then Estate Transfer the area to somewhere that'll consume him and his legacy crap   Oh, and if you wanna be a real bastard, try and Magic Jar him, and THEN drop both back into the AMF and shatter the phylactery.

[Unbeliever]

Why all the fromage here?  Its a fighter in an antimagic field.  A known problem with a low level solution.   The only possible issue is his weapon and armor may give him some abilities you don't find on a Colossus.  Like flight.  But probably not.

Seriously, unless his two whole magic items give him flight or a host of immunities a character with a decent EX flight and a pile of alchemical items can ruin his day.

Others have said this, but "arrows?" was my first thought.  I don't think it's an incredibly difficult thing to do. 

I have kind of mixed feelings about this character.  On the one hand, I kind of like the idea of a high level fighter-type being able to more or less force people to actually fight him.  On the other hand, I hate AMF and it's a gigantic headache. 

But, yeah, long range arrow attacks, or a sufficiently sneaky rogue/scout type (as I doubt his non-magical spot bonuses are crazy good).  Fight stabbing with stabbing.

[ketaro]

Invoke Magic.

[Braininthejar]

lure him underground, cast earhtquake. adamantine weapons might cut through rock, but they won't help you when you're underneath and running out of air (I assume he has the hitpoints to survive the collapse)

[Mithril Leaf]

Might I suggest a build involving Red Wizard, Reserves of Strength, Arcane Thesis, and Hail of Stone?

[SorO_Lost]

Frankly, there are no real rules on cosmology and you'd be making it all up anyways, So I just use those rules. They are as good as any others.

I don't think you understand dimensions.
This is also the second cosmology post in a like two days. Do we need a Reddit-style ELI5 thread? I know GH's pretty well and can cover DL too.

@Topic, Gish it up. Always fun to see a Spellcaster more powerful than a Fighter in an AMF.