Well there’s your mistake: raptors are nerfed so their pounce can’t do much, and they’re still glass canons. A Gen2 Rex won’t fair well either, since it’s missing that extra power from its Epic counterpart. Sometimes power isn’t everything (though it sounds like your dinos could use some leveling); believe it or not, you can counter a Sino with other tanks. If you have an Immune Dino (Ankylocodon or Postime, for example), you’re even better off. It takes time creating effective strategies, but you’ll get there. For it to be faster than a raptor would mean it was able to Insta Charge, or the player us a hacker if they were able to be that fast. Now faster than Trex, yes. If you got stunned by it, that also explains things. Pay attention to your surroundings and what dinos can do. You’ll find ways around them, even if it’s unorthodox.