Tell me in I go wrong
So a wizard with a fairy dragon familiar casts Elemental Body I using share spell to cast it on his familiar
The fairy dragon's AC starts at:
18 (+3 Dex, +1 dodge, +2 natural, +2 size)
no change in it's dex or dodge
+4 natural replacing the old +2 natural
changing from tiny to small size from +2 to +1
So, the final AC is:
19 (+3 Dex, +1 dodge, +4 natural, +1 size)
Is that right?
Yes.