Cut Your 2D Draw Calls With Sprite Atlas

Every sprite pulling from a different texture counts as a separate draw call, even small ones like UI icons or repeated enemy sprites. On a 2D project with a decent number of assets, this adds up in ways that don't show up until you actually check the Profiler and wonder why draw calls are high for how simple the scene looks.

Sprite Atlas packs multiple sprites into a single texture at build time:

Window > 2D > Sprite Atlas > Create New Sprite Atlas
// Drag sprite folders into the "Objects for Packing" list
// Enable "Include in Build"

Once sprites share an atlas, Unity batches them into a single draw call instead of one per sprite, assuming they also share material and sorting layer. Visuals stay identical, draw call count drops.

Easy one to underestimate. It doesn't take a massive asset count before this actually matters, especially on mobile where draw calls are a bigger bottleneck than on desktop.