He has slow movement speed but attacks non-stop with high damage (short range, Area Attack). He only gets knocked back when he dies.
Dagshund attacks non-stop and has a strong Area Attack. However, this enemy has a fairly slow attack animation, so it is pretty hard for him to advance. The best thing to do would be to spam defensive units (Cat, Tank Cat, etc...) while having a Bahamut Cat to take him out. Stacking Lizard Cats or Salon Cats can also work if you have enough meatshields to stall the Dagshund. This enemy isn't intimidating alone, but is usually spawned in groups or just spawned rapidly when included in a level.