This asset lets you design your 2D Map/Level/Puzzle easier

Features:
-Snapping/Unsnapping from the 2D grid
-Brush Insertion
-Area Insertion
-Brush Deletion
-Area Deletion
-Several Layers
-Layer Re-arrangement

Steps to use it:
1.Import the assets
2.Put the prefabs you want to use inside the 'Resources' folder
3.Open the Map Editor window
4.Make your map!

See Video for clarity.

Also, this tool seemless integrates with unity so that you can swap between building your own map, and selecting/changing the objects you put in it instantly.