Yay! I figured out how to get Numerological Persecution in the set by giving it the "Expensive creature kill slot" and attaching it to a spiced up version of Link's Gorgon Hierarch.

This version of Chain is a descendant of the Heirarch and should be of greater focus than the actual ability on the card. Unlike Link's card which asked for black creatures, this thing tags along anything as long as it is cheaper than the base spell (at least in this set). I know Wizards doesn't like to mention the stack on cards... if we can find a way to say this without using that word, I'd be happy. One way to do that is to allow you to cast the spell, which may not work due to timing issue... I don't know. I do know that casting the spell would let you chain into chain... which I think most people would prefer, and shouldn't break the mechanic since we're the ones deciding what abilities get chain.

Also: Hypergenesis. But I stopped caring about that problem years ago.

The simplest would be:

Chain 4: You may cast the next spell this turn without paying for it, as long as its CMC is 4 or less.

Doesn't put it on the stack before this spell; but does it actually matter?

I don't know. Part of the oddity of they way you wrote it is that I can cast this spell before combat, get into combat, do a bunch of stuff after combat, then play my spell for free. Even if you don't change phases that can be jarring. What if the Chain spell was need to trigger a "Draw a card" effect, you drew a card, it had a casting cost of 4 or less, so you played it for free? Does that feel wrong to you?

I think, ideally, you'd want both spells to go off at the same time (the order means nothing to me, however). Failing to be able to do that, though, I think I like your method better than mine, Vitenka.

Oh, also one more thing. Should this card say "odd power, even toughness"? It would let us bypass questions about whether zero is an even number...

It's fine to leave chain as it is and worry about templating later.

"When you cast this spell, you may cast another card from your hand with CMC <=4 without paying its mana cost" although that's a bit long? And yeah, ideally it would avoid 0-cost things, but we should be able to work something out later.

I'm not sure about P/T. I chose even/odd so there'd be the symmetry of them both counting the lowest possbile number, but it probably doesn't make much difference. I find it hard to believe people are confused whether 0 is even (you can argue that it's not a number) but I know that that actually isn't obvious if you're not used to maths.

­Ashling's Prerogative to the rescue! :P (Specifically its reminder text.)

­:) But that does suggest that we maybe shouldn't have "even" without the reminder, alas. We shouldn't worry about it until we're templating though.

Maybe the name should just be "squaring the circle"?

But... But... But...! You can't square the circle!

But you can't circle the square either, if by "circling the square" you mean constructing a circle with the same area as a given square using only a compass and a straight edge :)

For that matter, I can believe black would sit around trying to square the circle, but it doesn't strike me as a colour that, when it discovers it's impossible with a compass and straight edge, wouldn't, well, redfine the problem a bit so it could cosntruct it :)

Flipped odd and even and changed the name to Square the Cirlce, which is an overdue change. Further proof that black will do anything to win... even recreate new mathematics to better fit its vision. ;)

I also thought about changing "Chain" to "Transcend" to make fun of the fact that pi is transcendental... the whole reason why you can't square the circle. But, the point of chain is flavor, and it isn't worth it for one goofy joke.

Circling the square is something pigeons do, though :)

And yes - blacks approach to impossible mathematical problems: a) Invent new mathematics. b) See Cthulhu. Invite him to come to tea. c) Go insaner. d) Kill the circle! e) And now it fits neatly into this square. If you cut its edges off. Procrustus would have made a great mathematician. f) Realise that the corners of the square allow the circle to escape through time itself!

I may have just been unlucky, but several times I found myself with this in hand and nothing much else I could cast with it. I'm not sure if that's just because I wasn't used to it and didn't plan ahead, or if it's inherently problematic in 5-cost removal spell.

I am finding it hard to like this card; it just reads very clunkily imho. I'm probably in a minority though :)

It pretty much reads "Scratch your head, then Destroy target creature"

I did get it to chain - it was nice, but not wonderfully game winning to do so.

Hmm... that's interesting. I think I went with 5 and 4 because it opened up the most possibilities without leading to degenerate combos. I can't help look at this card and think to myself "People like Coal Stoker. People should like this card. After all, if you have a 5cc creature kill spell, wouldn't you normally play it as soon as you have access to 5 mana"?

But, I got to be honest, I don't know why people like Coal Stoker so much. I think it's the whole package more than the ability. And storm is in Timespiral, and Coal Stoker seems fair with storm.

On top of that, if black has a 'fortification' theme, it's bound to either paly mid-game or control. This version of Chain does excite me, but I feel like it belongs in Gruul, Boros or Rakdos, not in Mono-Black. Without, either a storm mechanic, or a feeling of rushing things onto the table, I think we're wasting a good mechanic on a color that doesn't want it. It does happen to accidently drop things like Cutwork Knight on the table, a thing you would have missed if you were playing mono only... but that seems more like a reason to pull it, than keep it.

In the intervening two years, 5-cost common removal spells have become much more the norm! Clearly we were just ahead of the game :P

However. Currently, this is the only Chain card at common. This seems like it should either be tweaked to have a couple more, or remove the keyword. And if we try to have just this mechanic on the card but non-keyworded, it seems very out of place in black. (I love the idea of sneaky sideways manafixing, but again, without the keyword it just looks like a strange ability in black.)

I kind of assumed Chain would be edited out, seeing as it doesn't really support our two black themes, and two is more than enough themes per color.

I'm open to suggestions to what this could be. I get the impression, though, that we can't keep the cool name and a flavorful ability that infers that cards are being maliciously chained together. Conflicting flavor doncha know. Either way, I assume we're aiming for 5cc creature removal.