Timbersaw

Use Whirling Death to secure last hits, harass opponents and at the same time cut some trees with it.

Consider putting a point in the Timber Chain early on tough lanes.

Keep Reactive Armor stacks high to be able to play aggressively and not fear for your life.

Check how many stick charges opponents have when you are going for a kill.

Consider tanking tower shots to keep the catapult alive.

Timbersaw isn't the best at rotating. You'd rather force opponents to come to you by playing aggressively.

Consider parking yourself in front of the tower opponents are looking to destroy. Build up armor stacks though.

Items that reduce healing and break effects are a big problem. Itemize against them and adjust playstyle.

When not much is happening, push out the sidelines even out of vision if necessary.

Pick up Aghanims Shard later in the game as it improves DPS and provides much needed building damage.

You don't necessarily want to go to late game, so try to close the game down before you fall off.

One player should buy Spirit Vessel against Timbersaw's reactive armor

Play agressively against Timbersaw before he reaches level 3, or only when his reactive armor stacks are low, otherwise avoid fighting him

Stay away from trees against Timbersaw

Timbersaw is strongest between 8 and 20 minutes, so avoid contesting him on the lane and try to pressure other lanes and heroes instead

Buy Silver Edge against Timbersaw's reactive armor, if you need an additional item to deal with him