For fun make up a really silly hybrid, it doesn’t have to be good just fun.
Apatomimus: Legendary Pinning Speed Controller
Some quirks of Biology just can’t happen. While a domestic cat and a mountain lion certainly have been known to produce offspring, the size difference between an Apatosaurus and the Ornithomimus truly makes this impossible without the divine intervention of a deranged genetic scientist.
Instant Pinning Strike: In an attempt to mimic the Evasive Strike of Ornithomimus this large creature moves so fast that it trips up its foe on accident, preventing their foe from escaping but certainly not dodging anything itself.
Instant Distraction: Something this size howling at you surely is more unsettling than an Ornithomimus
Immune to Stun
Immune to Deceleration