LEFAVE / FIREBIRD TV

DEMON SWEEPER

Demons10

Flags0

Safe squares0 / 71

Loading game…The game needs its page CSS and footer loader.

How to play

Clear every safe square without revealing a demon. Each number counts demons in the eight surrounding squares, including diagonals. Empty areas open together.

Your first reveal and its neighboring squares are safe. Select Flag to mark a suspected demon, then switch back to Reveal to keep playing. A flagged square cannot be opened until you remove its flag.

When the flags around an open number match that number, reveal the number again to open its other neighbors. Wrong flags can still uncover a demon. Some boards require a guess.

Mouse: left-click uses the selected action; right-click flags a square. Keyboard: Tab to the board, arrow keys to move, Enter or Space for the selected action, F to toggle a flag.

Difficulty changes apply to your next board. Download Board unlocks after a win or loss and saves a square result image. You can also copy sample Community post text and open LeFave's Community wall. No timer, sign-in, or connection to the livestream.

(()=>{
'use strict';
const DS_LEVELS = Object.freeze({easy:10, medium:15, hard:20});
function dsNeighbors(i) {
const out=[], r=Math.floor(i/9), c=i%9;
for(let y=-1;y<=1;y++) for(let x=-1;x<=1;x++) {
if((x||y)&&r+y>=0&&r+y<9&&c+x>=0&&c+x<9) out.push((r+y)*9+c+x);
}
return out;
}
function dsRandomInt(max) {
if(globalThis.crypto && globalThis.crypto.getRandomValues) {
const a=new Uint32Array(1), limit=4294967296-4294967296%max;
do { globalThis.crypto.getRandomValues(a); } while(a[0]>=limit);
return a[0]%max;
}
return Math.floor(Math.random()*max);
}
class DemonBoard {
constructor(level='easy', random=dsRandomInt) {
if(!Object.hasOwn(DS_LEVELS,level)) throw new Error('Unknown difficulty.');
this.level=level; this.random=random; this.total=DS_LEVELS[level];
this.state='ready'; this.first=-1; this.hit=-1; this.ended='';
this.cells=Array.from({length:81},()=>({m:false,r:false,f:false,n:0}));
}
get done(){ return this.state==='won'||this.state==='lost'; }
get safe(){ return this.cells.filter(c=>c.r&&!c.m).length; }
get flags(){ return this.cells.filter(c=>c.f).length; }
valid(i){ return Number.isInteger(i)&&i>=0&&i<81; }
plant(i) {
const protect=new Set([i,...dsNeighbors(i)]);
const choices=Array.from({length:81},(_,k)=>k).filter(k=>!protect.has(k));
for(let k=choices.length-1;k>0;k--) {
const j=this.random(k+1);
if(!Number.isInteger(j)||j<0||j>k) throw new Error('Invalid random source.');
[choices[k],choices[j]]=[choices[j],choices[k]];
}
choices.slice(0,this.total).forEach(k=>{this.cells[k].m=true;});
this.cells.forEach((c,k)=>{c.n=dsNeighbors(k).filter(j=>this.cells[j].m).length;});
this.first=i; this.state='playing';
}
flood(indices) {
const stack=indices.slice(), seen=new Set();
while(stack.length) {
const i=stack.pop(); if(seen.has(i)) continue; seen.add(i);
const c=this.cells[i]; if(c.r||c.f||c.m) continue;
c.r=true; if(c.n===0) stack.push(...dsNeighbors(i));
}
}
settle() {
if(this.safe===81-this.total) {
this.state='won'; this.cells.forEach(c=>{if(c.m)c.f=true;});
this.ended=new Date().toISOString();
}
}
lose(i){ this.hit=i; this.state='lost'; this.ended=new Date().toISOString(); }
reveal(i) {
if(!this.valid(i)||this.done) return false;
const c=this.cells[i]; if(c.f) return false;
if(c.r) return this.chord(i);
if(this.state==='ready') this.plant(i);
if(c.m) this.lose(i); else { this.flood([i]); this.settle(); }
return true;
}
flag(i) {
if(!this.valid(i)||this.done||this.cells[i].r) return false;
this.cells[i].f=!this.cells[i].f; return true;
}
chord(i) {
if(!this.valid(i)||this.done) return false;
const c=this.cells[i], ns=dsNeighbors(i);
if(!c.r||!c.n||ns.filter(j=>this.cells[j].f).length!==c.n) return false;
const todo=ns.filter(j=>!this.cells[j].r&&!this.cells[j].f);
if(!todo.length) return false;
const mine=todo.find(j=>this.cells[j].m);
if(mine!==undefined) this.lose(mine); else {this.flood(todo); this.settle();}
return true;
}
json() {
return JSON.stringify({v:1,level:this.level,state:this.state,first:this.first,hit:this.hit,ended:this.ended,
m:this.cells.map(c=>+c.m),r:this.cells.map(c=>+c.r),f:this.cells.map(c=>+c.f)});
}
static restore(text, random=dsRandomInt) {
try {
if(typeof text!=='string'||text.length>5000) return null;
const d=JSON.parse(text);
if(!d||d.v!==1||!Object.hasOwn(DS_LEVELS,d.level)||!['ready','playing','won','lost'].includes(d.state)) return null;
if(!['m','r','f'].every(k=>Array.isArray(d[k])&&d[k].length===81&&d[k].every(v=>v===0||v===1))) return null;
const b=new DemonBoard(d.level,random);
if(!Number.isInteger(d.first)||!Number.isInteger(d.hit)||typeof d.ended!=='string') return null;
b.state=d.state;b.first=d.first;b.hit=d.hit;b.ended=d.ended;
b.cells.forEach((c,i)=>{c.m=!!d.m[i];c.r=!!d.r[i];c.f=!!d.f[i];c.n=dsNeighbors(i).filter(j=>d.m[j]).length;});
if(b.cells.some(c=>c.r&&(c.m||c.f))) return null;
const count=d.m.reduce((s,n)=>s+n,0);
if(b.state==='ready') {
if(count||b.safe||b.first!==-1||b.hit!==-1||b.ended) return null;
} else {
if(count!==b.total||!b.valid(b.first)||!b.cells[b.first].r) return null;
if([b.first,...dsNeighbors(b.first)].some(i=>b.cells[i].m)) return null;
if(b.state==='won'&&(b.safe!==81-b.total||b.cells.some(c=>c.m&&!c.f))) return null;
if(b.state!=='won'&&b.safe>=81-b.total) return null;
if(b.state==='lost') {
if(!b.valid(b.hit)||!b.cells[b.hit].m||b.cells[b.hit].f) return null;
} else if(b.hit!==-1) return null;
if(b.done ? !Number.isFinite(Date.parse(b.ended)) : !!b.ended) return null;
}
return b;
} catch {return null;}
}
}
const root=document.getElementById('fb-ds');
if(!root||root.dataset.ready) return;
root.dataset.ready='1';
const ui=name=>root.querySelector('[data-ui="'+name+'"]');
const SESSION='firebird.demonSweeper.board.v1', PREF='firebird.demonSweeper.level.v1';
function readStore(store,key){try{return window[store].getItem(key);}catch{return null;}}
function writeStore(store,key,value){try{window[store].setItem(key,value);}catch{}}
let pending=readStore('localStorage',PREF)||'easy';
if(!Object.hasOwn(DS_LEVELS,pending)) pending='easy';
let board=DemonBoard.restore(readStore('sessionStorage',SESSION))||new DemonBoard(pending);
let mode='reveal', active=0, lastPointer='mouse', art={}, ready=false, result=null, generation=0;
const flagSvg='<svg class="ds-flag" viewBox="0 0 40 50" aria-hidden="true"><path d="M9 46V4M5 46h20" fill="none" stroke="#050508" stroke-width="8" stroke-linecap="round"/><path d="M9 46V4M5 46h20" fill="none" stroke="currentColor" stroke-width="4" stroke-linecap="round"/><path d="M11 5h24l-8 10 8 10H11Z" fill="currentColor" stroke="#050508" stroke-width="2"/></svg>';
const crossSvg='<svg class="ds-cross" viewBox="0 0 40 40" aria-hidden="true"><path d="M6 6 34 34M34 6 6 34" stroke="#050508" stroke-width="10"/><path d="M6 6 34 34M34 6 6 34" stroke="currentColor" stroke-width="5"/></svg>';
const tiles=Array.from({length:81},(_,i)=>{
const b=document.createElement('button'); b.type='button'; b.className='ds-tile';
b.dataset.cell=String(i);b.tabIndex=i===0?0:-1;ui('board').appendChild(b);return b;
});
function coord(i){return String.fromCharCode(65+i%9)+(Math.floor(i/9)+1);}
function titleCase(s){return s[0].toUpperCase()+s.slice(1);}
function notice(s){ui('notice').textContent=s;}
function setActive(i,focus=false){
tiles[active].tabIndex=-1;active=i;tiles[i].tabIndex=0;if(focus)tiles[i].focus();
}
function selectMode(value){
mode=value;root.querySelectorAll('[data-mode]').forEach(b=>b.setAttribute('aria-pressed',String(b.dataset.mode===mode)));
}
function chooseLevel(value){
pending=value;writeStore('localStorage',PREF,pending);
root.querySelectorAll('[data-level]').forEach(b=>b.setAttribute('aria-pressed',String(b.dataset.level===pending)));
const changed=board.level!==pending;ui('pending').hidden=!changed;
ui('pending').textContent=changed?'Next board: '+titleCase(pending)+'. Current board: '+titleCase(board.level)+'.':'';
}
function render(){
root.dataset.state=board.state;
ui('demons').textContent=String(board.total);ui('flags').textContent=String(board.flags);
ui('safe').textContent=board.safe+' / '+(81-board.total);
ui('board-label').textContent=board.level.toUpperCase()+' / 9 × 9';
tiles.forEach((b,i)=>{
const c=board.cells[i], mine=board.done&&c.m, wrong=board.done&&c.f&&!c.m;
b.className='ds-tile'+(c.r?' is-open n-'+c.n:'')+(c.f?' is-flagged':'')+(mine?' is-mine':'')+(board.hit===i?' is-hit':'')+(mine&&c.f?' is-correct':'')+(wrong?' is-wrong':'');
b.setAttribute('aria-disabled',String(!ready||board.done));
let label=coord(i)+'. ';
if(c.r){b.textContent=c.n?String(c.n):'';label+=c.n?c.n+' adjacent demons.':'Empty.';}
else {
b.innerHTML='';const img=document.createElement('img');img.src=(mine?art.demon:art.cube)?.src||'';
img.alt='';img.setAttribute('aria-hidden','true');img.draggable=false;b.appendChild(img);
if(c.f&&!wrong)b.insertAdjacentHTML('beforeend',flagSvg);
if(wrong)b.insertAdjacentHTML('beforeend',crossSvg);
label+=mine?'Demon.' : wrong?'Incorrect flag.':c.f?'Flagged.':'Covered. LeFave icon.';
if(mine&&c.f)label+=' Correctly flagged.';
if(board.hit===i)label+=' This square ended the game.';
}
b.setAttribute('aria-label',label);
});
const headline={ready:'BOARD READY',playing:'KEEP SWEEPING',won:'BOARD CLEARED',lost:'DEMON FOUND'};
ui('result-title').textContent=headline[board.state];
ui('result-detail').textContent=board.state==='ready'?'Your first reveal is safe.':board.state==='playing'?board.safe+' safe squares cleared.':board.state==='won'?'Every safe square cleared. All demons found.':'The demon was hiding behind LeFave at '+coord(board.hit)+'.';
root.querySelectorAll('[data-mode]').forEach(b=>{b.disabled=board.done;});
ui('new').disabled=!ready;ui('board').setAttribute('aria-busy',String(!ready));
writeStore('sessionStorage',SESSION,board.json());chooseLevel(pending);
}
function move(i,kind){
if(!ready||board.done||!board.valid(i)) return;
setActive(i);
const changed=kind==='flag'?board.flag(i):board.reveal(i);
if(changed){render();if(board.done)prepareResult();}
}
function clearResult(){
generation++;if(result)URL.revokeObjectURL(result.url);result=null;
ui('download').disabled=true;ui('image-actions').hidden=true;ui('community').hidden=true;ui('preview').hidden=true;
ui('view').setAttribute('aria-expanded','false');ui('preview-image').removeAttribute('src');ui('caption').value='';notice('');
}
function newBoard(){
clearResult();board=new DemonBoard(pending);selectMode('reveal');setActive(0);
ui('confirm').hidden=true;render();ui('new').focus();
}
root.querySelectorAll('[data-level]').forEach(b=>{b.onclick=()=>chooseLevel(b.dataset.level);});
root.querySelectorAll('[data-mode]').forEach(b=>{b.onclick=()=>selectMode(b.dataset.mode);});
ui('board').addEventListener('pointerdown',e=>{lastPointer=e.pointerType||'mouse';});
ui('board').addEventListener('click',e=>{const b=e.target.closest('[data-cell]');if(b)move(Number(b.dataset.cell),mode);});
ui('board').addEventListener('contextmenu',e=>{
const b=e.target.closest('[data-cell]');if(!b)return;e.preventDefault();
if(lastPointer!=='touch')move(Number(b.dataset.cell),'flag');
});
ui('board').addEventListener('focusin',e=>{const b=e.target.closest('[data-cell]');if(b)setActive(Number(b.dataset.cell));});
ui('board').addEventListener('keydown',e=>{
const b=e.target.closest('[data-cell]');if(!b)return;
const i=Number(b.dataset.cell),r=Math.floor(i/9),c=i%9;let j=i;
if(e.key==='ArrowLeft')j=r*9+Math.max(0,c-1);
else if(e.key==='ArrowRight')j=r*9+Math.min(8,c+1);
else if(e.key==='ArrowUp')j=Math.max(0,r-1)*9+c;
else if(e.key==='ArrowDown')j=Math.min(8,r+1)*9+c;
else if(e.key==='Home')j=e.ctrlKey?0:r*9;
else if(e.key==='End')j=e.ctrlKey?80:r*9+8;
else if(e.key.toLowerCase()==='f'){e.preventDefault();move(i,'flag');return;}
else return;
e.preventDefault();setActive(j,true);
});
ui('new').onclick=()=>{
if(board.state==='playing'||(board.state==='ready'&&board.flags)){
ui('confirm-label').textContent='Replace this board with a new '+titleCase(pending)+' board?';
ui('confirm').hidden=false;ui('keep').focus();
}else newBoard();
};
ui('confirm-new').onclick=newBoard;
ui('keep').onclick=()=>{ui('confirm').hidden=true;ui('new').focus();};
ui('download').onclick=()=>{
if(!result)return;
const a=document.createElement('a');a.href=result.url;a.download=result.name;
root.appendChild(a);a.click();a.remove();notice('PNG ready. Use View result image if your browser opens it instead of saving.');
};
ui('view').onclick=()=>{
ui('preview').hidden=!ui('preview').hidden;ui('view').setAttribute('aria-expanded',String(!ui('preview').hidden));
};
ui('share').onclick=async()=>{
if(!result||!navigator.share)return;
try{await navigator.share({files:[result.file],title:'Demon Sweeper — '+titleCase(board.state==='won'?'cleared':'defeated')});}
catch(e){if(e.name!=='AbortError')notice('Sharing is unavailable here. Use Download Board or View result image.');}
};
const COMMUNITY='https://www.youtube.com/@DJLeFave/community';
const pageUrl=()=>{try{return location.href.split('#')[0].split('?')[0];}catch{return 'https://djlefave.com/';}};
function captionVariants(b){
const safe=b.safe,total=81-b.total,level=titleCase(b.level),url=pageUrl();
if(b.state==='won')return [
`I cleared ${level} Demon Sweeper! 😈\n${safe}/${total} safe squares cleared with ${b.total} demons on the board.\n\nThink you can beat it?\nPlay Demon Sweeper: ${url}`,
`${level} Demon Sweeper: cleared. 😈\n${b.total} demons. ${total} safe squares. I survived all of them.\n\nYour turn: ${url}`,
`I actually survived Demon Sweeper. 😈\nCleared ${safe}/${total} safe squares on ${level}.\n\nCan you do it? ${url}`
];
return [
`A demon got me in Demon Sweeper 😈\nI made it through ${safe}/${total} safe squares on ${level}.\n\nThink you can survive longer?\nPlay Demon Sweeper: ${url}`,
`I trusted the wrong square. 😈\n${safe}/${total} safe squares on ${level} before Demon Sweeper got me.\n\nYour turn: ${url}`,
`Demon Sweeper claimed another victim. 😈\n${level} — ${safe}/${total} safe squares cleared.\n\nCan you beat my run? ${url}`
];
}
function setCaption(randomize=false){
if(!board.done)return;const variants=captionVariants(board);let index=0;
if(randomize){index=dsRandomInt(variants.length);if(variants.length>1&&ui('caption').value===variants[index])index=(index+1)%variants.length;}
ui('caption').value=variants[index];
}
ui('copy-caption').onclick=async()=>{
const text=ui('caption').value.trim();if(!text)return;
try{await navigator.clipboard.writeText(text);notice('Community post text copied.');}
catch{ui('caption').focus();ui('caption').select();try{document.execCommand('copy');notice('Community post text copied.');}catch{notice('Post text selected. Copy it, then open Community.');}}
};
ui('random-caption').onclick=()=>setCaption(true);
ui('community-wall').onclick=()=>{window.open(COMMUNITY,'_blank','noopener,noreferrer');};
function rounded(ctx,x,y,w,h,r){
ctx.beginPath();ctx.moveTo(x+r,y);ctx.arcTo(x+w,y,x+w,y+h,r);ctx.arcTo(x+w,y+h,x,y+h,r);ctx.arcTo(x,y+h,x,y,r);ctx.arcTo(x,y,x+w,y,r);ctx.closePath();
}
function box(ctx,x,y,w,h,fill,stroke,r=10,line=1){
rounded(ctx,x,y,w,h,r);ctx.fillStyle=fill;ctx.fill();
if(stroke){ctx.strokeStyle=stroke;ctx.lineWidth=line;ctx.stroke();}
}
function paintFlag(ctx,x,y,size,color){
ctx.save();ctx.translate(x,y);ctx.scale(size/40,size/40);
ctx.lineJoin='round';ctx.lineCap='round';
for(const [stroke,width] of [['#050508',7],[color,3]]){
ctx.strokeStyle=stroke;ctx.lineWidth=width;ctx.beginPath();ctx.moveTo(9,4);ctx.lineTo(9,38);ctx.moveTo(4,38);ctx.lineTo(21,38);ctx.stroke();
}
ctx.fillStyle=color;ctx.strokeStyle='#050508';ctx.lineWidth=2;ctx.beginPath();
ctx.moveTo(11,5);ctx.lineTo(35,5);ctx.lineTo(27,14);ctx.lineTo(35,23);ctx.lineTo(11,23);ctx.closePath();ctx.fill();ctx.stroke();ctx.restore();
}
function paintCross(ctx,x,y,size){
ctx.save();ctx.lineCap='round';
for(const [color,width] of [['#050508',11],['#ff00bc',6]]){
ctx.strokeStyle=color;ctx.lineWidth=width;ctx.beginPath();ctx.moveTo(x,y);ctx.lineTo(x+size,y+size);ctx.moveTo(x+size,y);ctx.lineTo(x,y+size);ctx.stroke();
}ctx.restore();
}
function resultCanvas(b){
const canvas=document.createElement('canvas');canvas.width=1080;canvas.height=1080;
const c=canvas.getContext('2d');if(!c)throw new Error('Canvas is unavailable.');
c.fillStyle='#08080d';c.fillRect(0,0,1080,1080);
c.fillStyle='#ff00bc';c.fillRect(54,34,76,6);c.fillStyle='#00ceff';c.fillRect(136,34,36,6);
const text=(s,x,y,size,color='#f7f7fa',weight=700)=>{c.font=weight+' '+size+'px Arial';c.fillStyle=color;c.fillText(s,x,y);};
text('LEFAVE / FIREBIRD TV',54,70,18,'#bdbdcc');
text('DEMON SWEEPER',50,130,58,'#f8f8fc',900);
c.drawImage(art.cube,928,48,96,96);
text(b.state==='won'?'BOARD CLEARED':'DEMON FOUND',54,177,31,b.state==='won'?'#00ceff':'#ff00bc',900);
text(b.level.toUpperCase()+'  /  9 × 9  /  '+b.total+' DEMONS',54,212,20,'#c2c2d0');
c.textAlign='right';text(b.safe+' / '+(81-b.total)+' SAFE',1026,212,20,'#00ceff');c.textAlign='left';
const x0=137,y0=214,size=87,gap=3,colors=['','#52d8ff','#72edaa','#ff779d','#bd9dff','#ffbb7f','#80efef','#f2f2ff','#cbcad6'];
box(c,129,206,823,823,'#050508','#3e3e4c',13,2);
b.cells.forEach((cell,i)=>{
const x=x0+(i%9)*(size+gap),y=y0+Math.floor(i/9)*(size+gap),mine=cell.m,wrong=cell.f&&!cell.m;
let fill=cell.r?'#101018':'#202026',stroke=cell.r?'#292933':'#555560',line=1.5;
if(mine){fill='#26101e';stroke=cell.f?'#00ceff':'#853560';}
if(wrong)stroke='#ff00bc';
if(i===b.hit){fill='#ad1265';stroke='#ff00bc';line=5;}
box(c,x,y,size,size,fill,stroke,7,line);
if(cell.r&&cell.n){c.textAlign='center';c.textBaseline='middle';text(String(cell.n),x+size/2,y+size/2+2,58,colors[cell.n],900);c.textAlign='left';c.textBaseline='alphabetic';}
else if(!cell.r){
c.save();if(cell.f&&!mine)c.globalAlpha=.34;c.drawImage(mine?art.demon:art.cube,x+3,y+3,size-6,size-6);c.restore();
if(cell.f&&!wrong)paintFlag(c,x+size*(mine?.62:.18),y+size*(mine?.57:.12),size*(mine?.37:.70),mine?'#00ceff':'#ff00bc');
if(wrong)paintCross(c,x+size*.26,y+size*.26,size*.48);
}
});
const footY=1060;
text(b.state==='won'?'ALL SAFE SQUARES CLEARED':'DEMON HIDING AT '+coord(b.hit),54,footY,20,b.state==='won'?'#00ceff':'#ff00bc',900);
c.textAlign='right';text('DJLEFAVE.COM',1026,footY,20,'#c6c6d3',900);c.textAlign='left';
return canvas;
}
async function prepareResult(){
if(!board.done)return;
const token=++generation, snapshot=DemonBoard.restore(board.json());
ui('download').disabled=true;notice('Preparing your result image…');
try{
const canvas=resultCanvas(snapshot);
const blob=await new Promise((resolve,reject)=>canvas.toBlob(b=>b?resolve(b):reject(new Error('PNG export failed.')),'image/png'));
if(token!==generation||!root.isConnected)return;
const date=snapshot.ended.replace(/[:.]/g,'-'),name='Demon-Sweeper-'+snapshot.level+'-'+snapshot.state+'-'+date+'.png';
const url=URL.createObjectURL(blob),file=typeof File==='function'?new File([blob],name,{type:'image/png'}):null;
result={url,name,file};ui('preview-image').src=url;ui('download').disabled=false;ui('image-actions').hidden=false;ui('community').hidden=false;setCaption(false);
let share=false;try{share=!!(file&&navigator.canShare&&navigator.canShare({files:[file]}));}catch{}
ui('share').hidden=!share;notice('');
}catch{notice('The image could not be prepared. Refresh this page to retry; this tab normally keeps your board.');}
}
async function loadArt(name){
const raw=String(root.dataset[name+'Art']||'').trim();
if(!/^data:image\/webp;base64,[A-Za-z0-9+/=]+$/.test(raw))throw new Error('Missing bundled artwork.');
const image=new Image();
await new Promise((resolve,reject)=>{image.onload=resolve;image.onerror=reject;image.src=raw;});
return image;
}
chooseLevel(pending);
Promise.all([loadArt('cube'),loadArt('demon')]).then(([cube,demon])=>{
if(!root.isConnected)return;
art={cube,demon};ready=true;
root.querySelectorAll('[data-art="cube"]').forEach(img=>{img.src=cube.src;img.hidden=false;});
render();if(board.done)prepareResult();
}).catch(()=>{
ui('result-title').textContent='ARTWORK NOT LOADED';
ui('result-detail').textContent='Check that the complete Demon Sweeper page HTML is saved, then refresh.';
ui('board').setAttribute('aria-busy','false');
});
})();

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