Why does Plusle appear in Minun hordes?

Question

On Route 5, I was grinding my Sentret to evolve into Ferret and I came across a horde of 4 Minun and 1 Plusle.

My Sentret is Level 13 with the ability Run Away and no held item.

Is this just a hidden Easter Egg, or how is this possible?

Answer 1

Two different Pokemon species may appear in the same horde. Plusle and Minun is one that does this, others include Seviper and Zangoose, Heatmor and Durant, and Carbink and Rogenrola. There are others besides these, but these are just the examples I can think of right now.
Different Pokemon seem to appear in the same horde when:
1) They are counterparts to each other - Minun and Plusle probably fall under this category, as does Tauros and Miltank
2) They have a long history of feuding with each other - this is the case with Zangoose and Seviper, and Heatmor and Durant. In these cases the Pokemon turn on each other in the battle and attack the opposite species, instead of your Pokemon.
3) They have similar designs - this is probably the case with Carbink and Rogenrola, although you could argue Plusle and Minun could fall in this category as well.

Hope this helped.

Comments

That's actually really cool how the groups like Zangoose and Seviper can turn on each other. Easier captures for me, hahaha.