Observation from watching the whole stream today:
1 Point advantage = 1 HP per second taken off of the opponent's nexus.
2 Point advantage = 1.5 HP/s
3 Point advantage = 2 HP/s
4 Point advantage = 2.5 HP/s
5 Point advantage = 5 HP/s
Update: Finally got to see the HP rate for 4 point advantage. 2.5 as I expected
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