Tentacruel

Tentacruel is a valuable lead in Ubers. It's able to set Toxic Spikes on nearly any lead, ensuring valuable chip damage on threats such as Groudon, Mewtwo, and Palkia. Its solid Speed tier enables it to outpace leads like Tyranitar and Giratina-O, and its high Special Defense lets it take attacks like Life Orb Rayquaza's Draco Meteor and Shaymin-S's Seed Flare. Lastly, it boasts effective hazard control. Its Poison typing enables it to remove Toxic Spikes upon entry to the field, and it can clear Spikes and Stealth Rock with Rapid Spin in some circumstances.

Unfortunately, Tentacruel has little use outside of leading. Its poor Defense and weak defensive typing hamper its ability to check anything, while its Special Attack is too low to be an effective offensive presence. Additionally, it lacks the durability of Forretress as a Rapid Spin user, making it occasionally challenging to keep Tentacruel useful over long games. Another point against it as a Rapid Spin user is its susceptibility to Giratina-O, which consistently forces it out with the threat of coverage such as Earthquake, Outrage, and Thunder, while blocking its ability to use Rapid Spin with its Ghost typing.