Use this to save yourself/teammate or disable enemy for 4 seconds. Sniper wants to Assasinate your friend, normally you astral sniper, but sometimes there is no time to go near sniper and astral him, so better astral your friend. With good time precision you can predict when sniper bullet almost hit your teammate, then astral him. This need practice and sometimes will make your mind grow bigger to predict what you can in Dota. Sniper lost his kill and Assasinate. Same with Vengeful Spirit wants to stun you, Astral yourself if your astral has 1 sec disable. So you not lost time and health.
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