Ambush is quite a symetrical map clearly divided equally down the centre.
A good Strategy is use mid to long range tactics to close down corridors which form the bulk of this map.
There are four good first floor sniper positions and a further one with a bit of sneeky glitching.
There are two buildings opposite each other in the centre of the map which offer excellent vantage points. You will have to be careful and use the cover as they are also a bullet magnet.
The centre building on the south side of the map, see map below, has several excellent sniping spots. The first is sat just behind the gas bottle. From here, if you are tight up to it you will be covered from all but the east side of the map which is easily covered. By inching back you can then see the opposite centre building, (this should be your first target at the start of a match as you will usually catch enemy snipers before they camp down). By edging back further you can look down the centre road for snipers or targets rushing up.
At the top of the stairs straight ahead you can either sit by the wall and snipe the northwest sniper spot or climb up the wall shoot over the roof. The roof spot covers most of the map but makes you a prime target.
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