Not A Bug Pokemon can get illegal egg move combinations in old gens of Random Battles

[Oxypad]

What type of bug are you reporting? Random Battles

What is the bug?
https://replay.pokemonshowdown.com/gen3randombattle-2044320815?p2

Skarmory has an illegal moveset. (Whirlwind + Drill Peck)

Gen3 Random.

Combinatorics of random battle moveset should check that Skarmory not get both moves on the same set, but I see how it could have happened.

Are you able to replicate it? If so, how?
N/A

 

[A Cake Wearing A Hat]

Illegal move combinations are allowed in Random Battles. This is intentional.