Presets are approximate CSS viewports, not verified S23 measurements. Browser bars, display settings and keyboard change the real available space. This previews layout and ordinary pointer input; it does not emulate Android touch or performance. Cyan collision outlines show live engine targets; flags and loose groundwork are decorative. Amber marks tower ground level. Metrics update while you play. Clicking outside the preview pauses the battle. Resizing preserves this preview. Reset starts a fresh playground; Try midgame opens a separate Battle 13 demo inside this preview. The playground and demo use separate assisted profiles. Selecting Campaign in the player lobby uses this browser’s normal local checkpoints.
Begin a battle in the preview to inspect the combat HUD. Menus are measured separately.