you can the opposing team flanking on tower 1 and tower 2. In the two towers are each a sniper rifle and a H2 BR. Use the two towers to reach the top mid with the SPNKr Bazooka on it. Bottom mid is the scattershot.
The lower area is quite open and offers little protection against opponents.
So you should try it on the four sides. These four sides are marked with letters and have 2x BR´s and 2x SMG´s.

Strongholds: The Strongholds areas located below bottom mid and in the two towers.

Mercy supported 1v1-4v4 fights. The perfect player count is 2v2 or 3v3.

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