need to fix entity here and make it endlessly spawn from the right side by chaotically moving in progression with platforms to the left side and then they should simply disappear by reaching the left side of canvas. entities need to multiply in count of enities spawned with player progression or just some basic timer, and enities should shot some projectiles which affects player square physics a little. output minified code: class Platform{constructor(x,y,w,h){this.x=x;this.y=y;this.w=w;this.h=h}collidesWith(obj){if(obj.y+obj.h<=this.y)return false;if(obj.y>=this.y+this.h)return false;if(obj.x+obj.w<=this.x)return false;if(obj.x>=this.x+this.w)return false;const objAbove=obj.y+obj.h-obj.vy<=this.y;const objBelow=obj.y-obj.vy>=this.y+this.h;const objLeft=obj.x+obj.w-obj.vx<=this.x;const objRight=obj.x-obj.vx>=this.x+this.w;if(obj.vy>0&&objAbove&&!objBelow){obj.y=this.y-obj.h;obj.vy=0;obj.jumping=false;return true}if(obj.vy<0&&!objAbove&&objBelow){obj.y=this.y+this.h;obj.vy=0;return true}if(obj.vx<0&&objRight){obj.x=this.x+this.w;obj.vx=0;return true}if(obj.vx>0&&objLeft){obj.x=this.x-obj.w;obj.vx=0;return true}return false}}class Player{constructor(x,y,w,h){this.x=x;this.y=y;this.w=w;this.h=h;this.vx=0;this.vy=0;this.jumping=false}move(keys){const friction=.9;const gravity=1;if(keys[87]&&!this.jumping){this.vy-=20;this.jumping=true}if(keys[68]){this.vx+=5}if(keys[65]){this.vx-=5}this.vx*=friction;this.vy+=gravity;this.x+=this.vx;this.y+=this.vy;if(this.x<0){this.x=0}if(this.y<0){this.y=0}if(this.x+this.w>canvas.width){this.x=canvas.width-this.w;this.vx=0}if(this.y+this.h>canvas.height){this.y=canvas.height-this.h;this.vy=0;this.jumping=false}}}class Entity{constructor(x,y){this.x=x;this.y=y;this.size=20;this.vx=-2+Math.random()-4;this.vy=-2+Math.random()4;this.projectiles=[];this.cooldown=0}move(){this.x+=this.vx;this.y+=this.vy;if(this.x<0||this.x+this.size>canvas.width)this.vx=-this.vx;if(this.y<0||this.y+this.size>canvas.height)this.vy=-this.vy;this.cooldown;if(this.cooldown<=0){this.projectiles.push({x:this.x+this.size/2,y:this.y+this.size/2,vx:-3,vy:0});this.cooldown=3}for(let i=0;i<this.projectiles.length;i++){this.projectiles[i].x+=this.projectiles[i].vx;this.projectiles[i].y+=this.projectiles[i].vy}}collidesWithPlayer(player){for(let i=0;i<this.projectiles.length;i++){const proj=this.projectiles[i];if(player.x<proj.x&&proj.x<player.x+player.w&&player.y<proj.y&&proj.y<player.y+player.h){player.vx+=proj.vx2;player.vy+=proj.vy2;this.projectiles.splice(i,1);i}}}draw(ctx){ctx.fillStyle=“red”;ctx.fillRect(this.x,this.y,this.size,this.size);ctx.fillStyle=“black”;for(const proj of this.projectiles){ctx.fillRect(proj.x,proj.y,5,5)}}}class Game{constructor(canvas){this.canvas=canvas;this.ctx=canvas.getContext(“2d”);this.platforms=[];this.player=new Player(100,100,50,50);this.scrollSpeed=4;this.platforms.push(new Platform(0,canvas.height-50,50,10));for(let i=0;i<10;i++){this.createRandomPlatform();this.entities=[];this.entitySpawnCooldown=0}this.keys={};document.addEventListener(“keydown”,evt=>{this.keys[evt.keyCode]=true});document.addEventListener(“keyup”,evt=>{delete this.keys[evt.keyCode]});requestAnimationFrame(this.update.bind(this))}createRandomPlatform(){const x=this.canvas.width;const y=Math.random()*this.canvas.height;const w=50+Math.random()*150;const h=10;this.platforms.push(new Platform(x,y,w,h))}update(){this.player.move(this.keys);for(let i=0;i<this.platforms.length;i++){this.platforms[i].collidesWith(this.player);this.platforms[i].x-=this.scrollSpeed}this.player.x-=this.scrollSpeed;if(this.platforms[this.platforms.length-1].x<this.canvas.width-500){this.createRandomPlatform()}this.entitySpawnCooldown;if(this.entitySpawnCooldown<=0){this.entities.push(new Entity(canvas.width,Math.random()*canvas.height));this.entitySpawnCooldown=100}for(const entity of this.entities){entity.move();entity.collidesWithPlayer(this.player);if(entity.x+entity.size<0){this.entities.shift()}}this.ctx.clearRect(0,0,this.canvas.width,this.canvas.height);for(let i=0;i<this.platforms.length;i++){let p=this.platforms[i];this.ctx.fillRect(p.x,p.y,p.w,p.h)}for(const entity of this.entities){entity.draw(this.ctx)}this.ctx.fillRect(this.player.x,this.player.y,this.player.w,this.player.h);requestAnimationFrame(this.update.bind(this))}}let canvas=document.createElement(“canvas”);canvas.width=window.innerWidth;canvas.height=window.innerHeight;document.body.appendChild(canvas);let game=new Game(canvas);