Beautiful variant but, in my opinion, this rule should be changed.I'm talking about when you checkmate. Even if the opposing king is in check, the opponent can continue playing if he in turn has the option to end the game. I don't find it right because being in check, he should protect the King. In this way the opponent does not bother to protect his King, continuing to play and Closing the game. Of course , a variant, but part of me, and a really absurd rule. What do you think?
It seems like the player is using the opportunity to explode the other king as a means of protecting their king since presumably the opposing army can't fight any longer without a king.
It keeps things interesting and fits the motif of the variant, I think.
In my opinion, this rule does make sense.
The player who can capture the other player's king first, wins. In Standard chess, when you're in check, you're forced to react because otherwise you'll lose your king. In Atomic, that isn't necessarily true as you can still be the first to kill the other's king even while you're in check.
Or, from another viewpoint: in Standard chess, "check" means "if I had an immediate second turn, I could capture your king". If we were to transfer that definition to atomic, any explosion threat would count as a "check". However, by the rules, you're allowed to just ignore that threat. (By this reasoning, you could also argue that it would make sense to add a rule that you _must_ protect against an explosion threat. But the rules, which we have taken from FICS, have been employed for so long now that changes like that seem unnecessary.)
(Side note: on some servers, such as ICC, atomic does not _have_ the concept of "check" at all. Meaning that only explosions count. That also has a few consequences, such as that you can castle "through check" (which you can't on Lichess), or that stalemated positions become lost because you're forced to move "in check".)
"I don't find it right because being in check, he should protect the King."
If your king is under threat, you should address that rather than putting your opponent in check. If you choose to leave your king exposed, then it is your own fault.
Atomic: follow the king around with your own king.
I haven't played even one game of atomic on lichess. I learnt the rules of both Antichess and Atomic together on FICS over a decade ago but concentrated on Antichess. The rule in question does make sense to me as well. I really like ProgramFOX's post here. While the antichess draw rule from FICS was not implemented here, the atomic rule was copied as is. It would have been nice if one of the other two options regarding check had been considered as well. Oops, it wouldn't have really mattered to me as I don't play atomic anyway. I'd like to improve at chess.
The ideologically pure concept is that the goal of chess is capturing the opponent king. All check and stalemate are alien, impure concepts introduced artificially to lend some "grace" to the king.
What is special in atomic, is that you can capture the opponent king without first attacking it. In pure normal chess an attack on the king means you have to do something about it, because if you attack back, your king will be captured first. This somehow gives you the wrong concept that checks have to be avoided in chess, which misconception is only amplified by the impure grace rules.
Even though I agree with everyone that the current atom rule does make sense (#3 said it all), I want to add that the proposed rule change (you can answer your king exploding by exploding the other king, making the game a draw, like in RK) also makes sense, and would be a fair atomic variant.
Most notably, it would affect a tremendous number of opening lines and possibly change the theoretical status of the variant (into a draw), revolutionizing opening play. That's not nothing.
remember every body
atomic variant have 3 way to win the game
1 check mate
2 give up
3 most important by explosion
explosion make diference with other variants
I agree there is an issue in ignoring a threat to win. My suggestion to improve this issue would be a new rule.
Mutually Assured Destruction:
If the enemy king is exploded, while your own king is in check, it results in a draw.