Variety equivalents: 
Breen 1128, Breen Decad 6-D

Notes:
The obverse die of this variety was also combined with Decad 6-F (1786 Maris 3-C)

Images courtesy of Superior Stamp & Coin

Known examples (2):
EF? (based on the photograph in Breen).  Ex - Morris - Brock - University of Pennsylvania - Ward - Newman, "160 grains"

Very Good-7" (illustrated below).  Ex - Superior Galleries New York ANA Sale, August 1-3, 2002, Lot 57, illustrated, where it was described as follows: "1786 Immunis Columbia/1785 Confederatio Mule. Breen-1128 Rarity-8. Very Good 7. Dark chocolate brown and steel. The surfaces are slightly rough, covered with very fine granularity and a couple small patches of shallow verdigris, most likely from being lost in soil for a while. The IMMUNIS COLUMBIA side is a few points sharper than the reverse, with a strong date and complete legend. The CONFEDERATIO side (reverse) is a bit weaker, but the date and legends are readable. There are a few light hairline scratches on both sides, the only notable one down through the N in CONFEDERATIO. One of only two known of this Wyon pattern, produced to help him obtain a contract to produce our earliest Federal coinage. (The other example is held in a museum.) Struck rotated slightly clockwise from a head-to-head di e orientation. Weight 131.2 grains."

Sources and/or recommended reading:
"Walter Breen's Complete Encyclopedia of U.S. and Colonial Coins" by Walter Breen