Tinker

Basic Strategy

 * Laser is an extremely powerful nuke that ignores magical resistance. Use it as primary source of damage for Tinker. Linken's Sphere blocks the blinding side effect but the target still takes damage.
 * Heat Seeking Missile has a really long range. You can spam it from a safe distance to harass enemy heroes.
 * March of the Machines is a perfect farming tool. It's a bit tricky to aim though. You can overlap several March of the Machines using Rearm to deal massive AOE damage.
 * Tinker is arguably the best solo mid hero. He can constantly harrass his lane opponent with Laser and Heat Seeking Missile forcing him to stay away from creeps. And if he gets pressured by roaming heroes he can always farm safely using his March of the Machines from afar.
 * You can stack commands by holding shift to prevent unintentional Rearm interruptions. Tinker will perform stacked commands right after finishing Rearm.
 * Boots of Travel is a commonly built item on Tinker. Used in conjunction with Rearm, it allows you to teleport around the map quickly.
 * Once Tinker gets Boots of Travel and Soul Ring, start teleporting back and forth between lanes and fountain to farm everything on the map.
 * Participate in ganks whenever you get a chance. "Missile, Laser, Rearm, Missile combo" should be enough to finish off any fleeing enemy early-mid game.
 * Always kill enemy silencers and disablers first because they can ruin your spell combos.
 * Tinker can permanently disable and kill enemy carries in the late game. Simply repeat "Scythe of Vyse, Missile, Laser, Rearm" cycle till your target is dead. Make sure you have sufficient mana pool and you're perfoming everything quick enough.
 * Another popular item to get as Tinker is the Dagon as it works well with Rearm to deal massive burst damage provided a sufficient mana pool is present. The combo of Dagon > Rearm > Dagon is deadly when paired with Heat Seeking Missile and Laser.

Trivia

 * Tinker's voice actor, Harry 'Hal' Robins, also voiced Dr. Isaac Kleiner in Half-Life 2. Many of Tinker's voice lines reference characters and events from the Half-Life universe.