user31663: I have heard that there is something like a 9 move sequence to force a draw in crazyhouse. Is there such a sequence?

user26072: Not only is there no "9 move sequence to force a draw" in Crazyhouse, but it is quite possible - rather likely in fact - that a draw cannot be forced in Crazyhouse in any number of moves, because Crazyhouse is a win for White.
The first thing to note about Crazyhouse is that it is a more, not less, complex game than chess in the sense of having a larger gametree: much larger, indeed, because for every piece you can drop, there are a great many empty squares you could probably drop it on (thus, the average branching factor of Crazyhouse is probably more than double that of chess). Crazyhouse is regarded as quite similar to Shogi in this sense. Gametree size isn't all that matters for strategic depth - how easily the gametree is pruned by a player also matters; there's no indication that Crazyhouse's tree is any easier to prune than that of standard chess.
All this to say, it's inconceivable that any human player of Crazyhouse could be anywhere near the game's theoretical skillcap. The best humans get clobbered by the best engines pretty much 100% of the time, like in chess. So much for a simple 9-move way to force a draw.
Now, there is also some evidence that Crazyhouse is a theoretical win for White. As AlphaZero improved at Shogi it was found that its win-rate as Black (the first-mover in Shogi) actually increased. I don't know much about the current engine scene in Shogi but I'd be interested to hear whether this trend has been sustained. In Crazyhouse, there is some evidence that as you increase the strength of engines, whether by lengthening the time-control or by using a better (more recent) engine, the White win-rate increases. Empirically, it seems fairly likely that you cannot force a draw in Crazyhouse at all. (At least, unless you're White, in which case you can probably force a win too; and in any case, these are far beyond the horizon of calculation for any human or currently feasible engine.)

31663: <p>I have heard that there is something like a 9 move sequence to force a draw in crazyhouse. Is there such a sequence?</p>
 26072: <p>Not only is there no &quot;9 move sequence to force a draw&quot; in Crazyhouse, but it is quite possible - rather likely in fact - that a draw cannot be forced in Crazyhouse in any number of moves, because Crazyhouse is a win for White.</p>
<p>The first thing to note about Crazyhouse is that it is a more, not less, complex game than chess in the sense of having a larger gametree: much larger, indeed, because for every piece you can drop, there are a great many empty squares you could probably drop it on (thus, the average branching factor of Crazyhouse is probably more than double that of chess). Crazyhouse is regarded as quite similar to Shogi in this sense. Gametree size isn't all that matters for strategic depth - how easily the gametree is pruned by a player also matters; there's no indication that Crazyhouse's tree is any easier to prune than that of standard chess.</p>
<p>All this to say, it's inconceivable that any human player of Crazyhouse could be anywhere near the game's theoretical skillcap. The best humans get clobbered by the best engines pretty much 100% of the time, like in chess. So much for a simple 9-move way to force a draw.</p>
<p>Now, there is also some evidence that Crazyhouse is a theoretical win for White. As AlphaZero improved at Shogi it was found that its win-rate as Black (the first-mover in Shogi) actually increased. I don't know much about the current engine scene in Shogi but I'd be interested to hear whether this trend has been sustained. In Crazyhouse, there is <a href="https://lichess.org/forum/game-analysis/is-crazyhouse-a-force-win-for-white?page=2" rel="noreferrer">some evidence</a> that as you increase the strength of engines, whether by lengthening the time-control or by using a better (more recent) engine, the White win-rate increases. Empirically, it seems fairly likely that you cannot force a draw in Crazyhouse at all. (At least, unless you're White, in which case you can probably force a win too; and in any case, these are far beyond the horizon of calculation for any human or currently feasible engine.)</p>
