Standard American-style crosswords have rotational symmetry in the squares. This one has rotational symmetry in the answers themselves. It's extraordinary. I think I actually yelled out loud when I finally realized what was going on.
For the acrosses, the top left corner begins with DAP. The bottom right ends with PAD. Then OGRE/ERGO, REED/DEER, and so on.
For the downs, it's DORA/AROD, AGES/SEGA, PRET/TERP.
And right in the middle, two palindromes STETS and RACECAR.
Every single letter in the top left has a matching letter in the bottom right. It's an insane feat of puzzle construction.
While it is, DAP/PAD both loosely fit the prompt "Fist bump" which made me incredibly impressed with the puzzle. I then tried to figure out what fairy tale featured an ERGO, and became slightly less impressed.