Maybe it just takes the tile, moves it one pixel, takes the row pixels that are lost after moving and puts it in the other (now empty) row.
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These are my eggs!
They need clicks to grow!

Step 1.
Go to Google Images and type in whatever you want a minipic of and hit search

Step 2.
Click Search tools and set Size to exactly 16x16

Step 3. (For animated minipics)
Set Type to Animated


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These are my eggs!
They need clicks to grow!