Blitzcrank vs Thresh

Fire Rocket Grab (Q) from a brush or a side angle: it grabs the first enemy hit, so you need a line without minions.

After a successful grab, cast Power Fist (E) right away: your next auto knocks the target into the air and deals double damage.

Sometimes engage without a grab: rush in with Overdrive (W), knock your target into the air with Power Fist (E), and save Rocket Grab (Q) for when they Flash away.

Use Mana Barrier (passive) to bait: at low health you get a shield based on your mana, enough to make a kill look easy.

In teamfights, save Rocket Grab (Q) for their carry and wait for them out of vision: grabbing them before the fight starts often decides it.

Keep minions between you and Thresh: Death Sentence (Q) stuns and pulls the first unit hit, so one minion is enough to block it.

Step up when Death Sentence (Q) misses you: he keeps its full cooldown, 19 to 9 seconds, which only goes down if the hook lands.

Don't stay in his range for no reason: Flay (E) charges his autos between hits, and a charged auto hits hard early on.

Avoid being the first to break a wall of The Box (R): that one slows and deals full damage. After that, the remaining walls deal no damage.