The title clues that this has to do with fairy chess pieces. A list can be found here. From the flavor text, we see that these are mate-in-1 puzzles for the team with the fairy piece (white) and should figure out which fairy chess piece is which. Each one is used exactly once.

1. Amazon (Queen + Knight). Ff3#.

2. Princess (Bishop + Knight). b4#.

3. Wazir ((0,1)-leaper). Fe4#.

4. Nightrider ((1,2)-rider). Qc6#.

5. Zebra ((2,3)-leaper). Fxd4#.

6. Imitator (Move: Queen, Capture: like piece captured). Fxc6#.

7. Mann (King, but not load-bearing). Fb4#.

8. Camel ((1,3)-leaper). Fe7#.

9. Ferz ((1,1)-leaper). Fb7#.

10. Alfil ((2,2)-leaper). Fc3#.

11. Fiveleaper ((0,5)-leaper + (3,4)-leaper). Ff1#.

12. Berolina pawn (Pawn, but movement for move and capture are switched). c3#.

13. Checker king (Kinged piece in checkers, capture is optional). Nxe6#.

14. Immobilizer (Queen, immobilizes pieces a king's move away). Rh4#.

15. Withdrawer (Queen, captures piece behind it). Fxb2#.

16. Zero ((0,0)-leaper). Qb6#.

17. Wizard (Alfil + Camel). Ff4#.

18. Threeleaper ((0,3)-leaper). Ff6#.

19. Grasshopper (Queen, but must hop over a piece and land in front of it). Fc4#.

Then we answer the question in the flavor text by looking at the fairy pieces’ final positions and extracting a letter from the letter grid for each one, giving COMBINE PERMUTATIONS.