What is our best anti-MEQ unit?

I’ll start right out by admitting than I’m very new, but my friend that got me into 40k runs an Imperial Fist successor and I really don’t want to get mowed down by him on a regular basis. Suggestions for good counters? He’s very shooty, complete with a las-predator, while I have two Start Collecting packs and plans for a Knight Warden and kastelan robots.