Keeper of the Light

Make sure pull camps are unblocked as lane is likely to be pushed due to Illuminate.

Be creative at positioning to be able to hit opponents with Illuminate.

Avoid hitting ranged creeps with level 1 Illuminate as it will become deniable.

Illuminate provides vision which can be used to check pillars for wards or Roshpit.

Keeper is fast and with Illuminate you can make multiple stacks at the same time.

Keeper is amazing at defending buildings while your cores can split push.

Avoid showing yourself at the start of the fight and align Illuminate's path over allies in Spirit Form for heals.

Make sure to provide Chakra Magic to an ally that benefits most from it after his spells were used.

When not much is happening, push out sidelanes with Illuminate. You don't even have to show yourself.

Make sure to pick up Aghanim's Scepter at reasonable time as this hero lacks control.

Use Blinding Light to push opponents under your tower or closer to your core if you can get a favourable trade.

Bring an Observer ward to your lane to see Keeper of the Light charging Illuminate.

Prevent Keeper of the Light from pulling as he will push with Illuminate and then look to pull.

Keeper of the Light is very squishy but really fast. One disable and he will drop low on HP.

Keeper of the Light is great at defending towers alone. Jump him or consider glyphing the wave.

Magic resistance and spell immunity items are great against Keeper of the Light.

Aghanim's Shard on Keeper of the Light grants Recall. He can teleport allied heroes to himself.