Crustle

Crustle has access to both Stealth Rock and Spikes, as well as Sturdy, making it an excellent suicide lead. In addition, its Bug / Rock typing gives it a good matchup against Xatu, which is a common anti-lead that can utilize Magic Bounce to prevent entry hazards from going up on the opponent's side of the field; Crustle's STAB moves prevent it from coming in safely, while its access to Rock Blast allows it to beat other leads such as Archeops. However, Crustle's low speed means that it's often Taunt bait, preventing it from setting up Stealth Rock or Spikes if hit by the move. Furthermore, Crustle is ridiculously one-dimensional, as opponents will know its set the majority of the time and will often send out a lead with good matchup against it, occasionally preventing it from doing its job.