https://github.com/photonstorm/phaser/blob/dev/src/geom/Ellipse.js#L196 this.width = this.x + value; should be changed to: this.width = value - this.x; https://github.com/photonstorm/phaser/blob/dev/src/geom/Ellipse.js#L238 this.height = this.y + value; should be changed to: this.height = value - this.y;