Ratings & Comments

I now also upgraded the general Diagram script to get more realistic piece values for this variant. It had a rather complex algorithm for determining the contribution of promotability to the piece value. Which would determine the ease of promotion based on counting the fraction of moves that would enter the promotion zone in (randomly generated) test positions, and assume the product of this ease and the promotion gain would determine the probability that this piece would indeed promote during the game. (Assuming that pieces with a less attractive promotion prospects would have to be traded away to clear the way for that.) This of course gave rather non-sensical results if there was no promotion zone at all. In that case the Diagram now assumes promotion on capture for promotable pieces (as specified by maxPromote). It then adds 50% of the promotion gain if this is positive, and subtracts 10% of the devaluation if it is a demotion (assuming there are ways to avoid it, but that this avoidance does make the piece less useful).

I added 'Campmate'.

@Daniel,

Now there's an interesting idea!

There is nothing wrong with the mechanism of summoning itself. What wrecks things is that you automatically get the Demon back in hand when it gets captured. That effectively makes it an 'iron piece'. Giving the opponent two moves, knowing that he has those, is too costly, though. In the opening you might get away with it, but in a typical middle-game position the opponent would use those to make a hit-and-run capture.

Furthermore, summoning a Demon for free seems too easy; in horror stories one typically has to make some sacrifice as part of a summoning ritual. Using this concept the following might work: to summon a Demon, the Mage should first capture a friendly piece. That will then 'activate' him for summoning a Demon in the next turn. But depending on what the opponent does in his turn, you might pass on the opportunity to summon, and do something else. That would waste the opportunity to summon, and you would only regain it by capturing another friendly piece.

This is looking better now, and I have unhid it.

“I am starting to suspect that this summoning business will sort of spoil the game. Because you get the Demons back whenever you lose them, at the cost of only a tempo.”

One thought I have been having is to make a summon cost two tempo: You can summon a piece, but when you do, your opponent gets an extra move.

Let’s imagine, for the sake of simplicity, a Seirawan Chess variant where instead of the “add the piece when moving a piece in the back rank” rule, the knight can summon the Elephant (Seirawan’s nomenclature for the R+N Cardinal/Marshal) next to it, and a bishop can summon a hawk (B+N, i.e. Archbishop), but each time a summoning is done it costs two tempo.

Here’s how a game could start out:

1. Nf3 d5
2. E@g3 e5,Nf6

We could write the score like this too, if preferred:

1. Nf3 d5
2. E@g3 e5
3. (Tempo lost after summoning) Nf6

Here, White opens with Nf3, Black responds d5

Next, White summons an Elephant on to g3 (I’m using Crazyhouse notation, which is fitting because Seirawan himself frequently plays Crazyhouse on Lichess). Because White has performed a summoning, Black now gets a bonus move, so Black moves e5 then Nf6.

If the other player responds to the summoning with a summoning as their first move, they don’t get the second bonus move. If they respond to the summoning with a summoning on their bonus move, the other player gets a bonus move, e.g.:

1. Nf3 Nc6
2. E@g3 E@b6

or

1. Nf3 Nc6
2. E@g3 d5,E@b6
3. e4,d4

I think the summoning mechanic is very unique and creative, but it might give White a won game, but maybe we can hobble it to keep it usable.