Subject: MN: Bifurcation

From: "Dunx (Duncan Ellis)" <DELLIS@U...>
Date: 24 Jun 98 15:11:30 +0100

I've been thinking about putting forward a Special Ruleset Proposal to 
allow Bifurcation, which I'm sure you would agree is a pretty important 
part of the MC culture. I just wanted to float these ideas past people to 
see how sea-worthy they are, and also to ask for suggestions on a thorny 
problem that might sink the whole thing. 

As an example (and unnecessary reminder), a typical bifurcated move in 
York-style MC is - 
Dunx: Victoria / Vauxhall 

The usual style of play requires that if one player bifurcates, then all 
others must follow suit. Furthermore, in order to win then both parts of 
the bifurcation must reach MC. 

Things that can happen to bifurcations include being created, being 
unified (ie collapsing a bifurcation back to a single thread), and having 
its degree increased (what might generically be termed n-furcation). 
Trifurcation, quadrifurcation, and even higher degrees have been achieved. 

So - how should this apply to Mornington Nomic? 

My thinking is that there should be two varieties of Bifurcation: of Piece, 
and of Game. I'll look at each of these in turn, starting with the easiest 
first. 

Piece Bifurcation (which I shall term Duplication from here 
on) is a way for the Player to gain another Piece on the board. The new 
Piece would spring into existence at the point at which the Duplication 
took place and would henceforth be independent. 

Each of the pieces would get a Move and would be identified by an index 
number suffix on the Player's name. The Pieces would Move in the order of 
their index numbers, but would both move on the same map. 

So, for instance if I were to play a Duplication - 

Dunx-1 : Victoria (VC) [Duplicate] 
Dunx-2 : [LV+2] Vauxhall (VC) 
... 
Dunx-1 : Oxford Circus (VC) 
Dunx-2 : [LV+1] Kennington (NT via VC) 

My thinking was that these Pieces would share Possessions, since they are 
really attributes of the Player rather than of the Piece, but that the 
Line Velocities would be independent. This brings up the thorny problem - 
there is currently only on LV value in the GSD per Player. I will address 
this further later. 

The advantages for a Player are that there are now two Pieces to gather 
token bonuses and the two could be a powerful attacking formation. 

The downside is that there are two Pieces paying Token costs! In order 
for a Player to win, e would have to get both of eir Pieces to MC, for 
instance. Similarly, there are multiple targets for Possession theft. 

Unifying a Duplication would be simple - just ensure that both Pieces to 
be rejoined are in the same place and, perhaps, have the same LV. 

As effectively an attacking Action, Duplication should have a Token cost 
associated with it (two Silvers?). 

Game Bifurcation would be handled in a similar way, except that all 
Players would gain an extra Piece and that extra Piece would be on a 
separate copy of the map. For the sake of sanity, I would suggest that 
Wild Stations, Knip, and Bridges are kept common though. 

The notation for Game Bifurcation should be similar to but not incompatible 
with that for Piece Duplication. My thinking was an ID letter prefix: 

A-Dunx : Victoria (VC) [Bifurcate] 
B-Dunx : [LV+2] Vauxhall (VC) 
... 
A-Dunx : Oxford Circus (VC) 
B-Dunx : [LV+1] Kennington (NT via VC) 

As with Duplication, Possessions should be shared with LV being 
independent. 

Triggering Bifurcation should, I think, be based more on a set of 
conditions than a Token cost eg travelling clockwise on the Circle with an 
LV in excess of 8. 

Unifying Bifurcation is less obvious than Duplication - I would have 
thought that one branch could say it wished to absorb or eliminate 
another. 

For a Bifurcated Game, once again both branches would need be won to win 
the whole Game - each Move to MC would close off that branch. This would 
effectively constitute a voluntary unification. 

You may gather from my choice of compatible notations that I think you 
should be able to combine these. Also note that there isn't anything 
to stop you logically from Duplicating or Bifurcating multiple times... 

Does this make any sense? I'm kean on this idea because it is conceptually 
very simple, but could work in combination with itself to make things jolly 
interesting. 

As I say, the LV independence issue is a real problem. The only thing I've 
managed to come up with is to try moving the LV value when a bifurcation 
effect is active, and to mark the token table with a blanking placeholder. 
For instance: 
B-Dunx (2) : [LV+2] Vauxhall (VC) 

... but that isn't very pretty at all. 

Any thoughts? 

-- 
Dunx 
IRL: Duncan Ellis, Senior Software Engineer, Business Modelers, Oracle 
<I work for Oracle, I don't speak for them>

---

From: "Jonathan L. Ellis" <mfmx4jle@f...>
Date: Wed, 24 Jun 1998 19:17:52 BST0GMT

> took place and would henceforth be independent. 

I'm not sure about this bit. After all, it's easier to gain Tokens 
than to lose them, and allowing one Player to Bifurcate without other 
Players doing so strikes me as getting an unfair advantage. 
Especially if the Bifurcated Player had control of the Drone as well 
- three pieces going around collecting Tokens. This is IMHO a bit 
much. Bringing in bifurcation is a good idea, though, and I like this 
bit about Game Bifurcation better...

> Wild Stations, Knip, and Bridges are kept common though. 

*snip* 
Great idea. I'd vote for that if I was going to be around to do so, 
which I'm not... I'd also suggest that all strands of a Bifurcation 
must take place within the single hour that a Player has to make eir 
Move (or two hours, if a Blue Token is paid, etc.) Strand A and 
Strand B, therefore, can only take up one hour between them...

> thought that one branch could say it wished to absorb or eliminate 

My suggestion is this: 
Any Player may unify the Bifurcation with the Action [Unifying 
Threads <X> and <Y>] (with no cost) by playing a Move which brings 
both eir Pieces together at the same Station, on the same Line, with 
the same Line Velocity and Line Direction.
If the Game is or was Bifurcated, and another Active Player's 
last move included [Unifying Threads <X> and <Y>] (where X and Y are 
threads of a Bifurcation, Trifurcation or greater number of split 
threads), then the Player whose Turn it is to Move must move eir 
Pieces from both relevant Threads to the same location and Line on 
that Move: if both Threads cannot achieve the same LV, then the lower 
value is used for that Player's next Turn.
If it is not possible for the Player to move both eir relevant 
Pieces to the same location on one move after a Reunifying move has 
been played, that Player must pay 2 Silver Tokens and play a move of 
[Home] in both threads, reunifying at the Home Station with an LV of 
zero. If e does not have enough Tokens to pay the penalty, e must 
pay them as soon as e can, splitting [Gold to Silver] if necessary.

{Comments: A forced unification, therefore, has both branches 
using a 30-minute Action, and therefore no other Actions permitted as 
it takes up the full hour... meanwhile, the "natural" unification, 
where both threads *can* move to the same Station and Line, pays no 
penalty.}

> effectively constitute a voluntary unification. 

I'd still suggest that a Bifurcated Player may not move to MC unless 
all threads can do so on a single Turn, each separately paying the 
Token cost of entering MC. 

> very simple, but could work in combination with itself to make things jolly 

Duplication I'm not keen on. I had some trouble in one of the 
challenge matches with an opponent who thought he could stay 
bifurcated while I was in a single thread... It's too unbalancing 
IMHO.

> B-Dunx (2) : [LV+2] Vauxhall (VC) 

Treat the two threads as separate Players (i.e. change the "Dunx" 
Player line to "A-Dunx" and a separate line underneath for "B-Dunx" - 
the Token totals being kept only in the A-Dunx line, but being 
altered for any relevant move by any of the Dunxes, or any Shunt of 
any Dunx by another Player. Then both halves can have independent 
LVs, but share Tokens and a Home. And both have to move within the 
hour allowed for one Player Move...
An A-[Player] may only Shunt or Shadow another A-[Player], not a 
B-[Player], and vice versa - but the Token Stacks, Knip, Bridges, 
Wild and any other Game States should be common to both, for ease of 
calculation and retention of sanity. 

Just my couple of suggestions...

Jonathan Ellis.

Jonathan L. Ellis <mfmx4jle@f...>