Sylveon

Sylveon has great Special Attack, impressive bulk, and a good movepool, all of which allow it to perform a number of roles effectively. It can be a great wallbreaker with Choice Specs thanks to its access to STAB Pixilate Hyper Voice. Its access to Heal Bell, Wish, and Calm Mind allow it to function as a cleric and bulky setup sweeper user. It has decent coverage options in Shadow Ball and Psyshock, the latter of which can hit Poison-types that would try to switch in on a Fairy-type attack. However, Sylveon's low Defense limits its defensive capabilities. Its low Speed makes it easy to revenge kill and means that it will often need to take a hit first before it can attack. Its good Special Defense makes this less of a problem, but physical attackers can still take advantage of it.