On attack vs defence maps, teleporters are critical. This means they are both a necessity for the defenders to speed up front line reinforcements as well as a key target for attackers to stop that flow. For spies, they should probably be targeted in preference even to sentry guns, since they are often a distance away from the engineer, and there’s always the teleporter entrance which can be taken out with little to no resistance, which will take some time to rebuild (entrance sapping doesn’t really apply for defenders). Of course you can target the engineer’s other buildings while he’s rebuilding.
Neither team should neglect either control point completely. Attackers should attack a single point with most of their team, but send a few to the other point as well, both to prevent all defenders from flocking a single point as well as to distract some of the defence when they see the point’s icon slowly being captured. Defenders should have at least a few guys at each point to prevent the attackers from getting an immediate foothold in either. Call for backup if you’re outnumbered at a point. Please, both teams, have at least 1 medic at each point (if any teammates are there).
Teams should have good communication about the locations of engineer buildings. Attackers need to know where sentry guns are so they don’t throw their lives away and so they can target them more effectively, and defenders should know if the attackers are setting up forward defences and/or teleporters, since these are good things to deprive them of.
Demomen are crucial for both sides, since there are only a few viable entrances to each point, and once inside there is a lot of cover for both teams. For defenders, a foothold in a point is best solidified by preventing any attackers from entering to resist, and few attackers are going to walk through 8 sticky bombs, so simply covering the main entrance with sticky bombs is an effective deterrent. The same goes for defenders – plugging an entrance with sticky bombs should, if not prevent attackers, at least make them think twice and run down the clock.
The roof of control point B is an exceptionally effective vantage point (covered again on the next page), so either attackers or defenders should aim to get themselves up there. Soldiers are more effective at range whereas demomen are unsurpassed at blocking doorways and clearing out enemy presence inside the capture zone. Offensive demomen should note that they can reach the roof with a single, well timed sticky bomb jump from the left entrance to B without even touching the dirt.
One of the most important things for defenders to remember when defending point C is that it can’t be captured so long as there is a defensive presence inside it. Thus having a heavy up the top with a dispenser and/or medic can be a very effective preventative measure. Look out for soldiers and demomen sniping from below and be extremely paranoid about spies.
As for attackers, it tends to be easier to attack C via the right-hand side entrance from B. Not only is it directly in line with the tower, it’s also closer to the defenders’ spawn and closer to the defensive places sentry guns are often built. Range is a defender’s greatest asset, since they can take pot shots at attackers and sentry guns don’t miss, while an attacker has to be precise to be effective. Cutting down the range on sentry gun emplacements allows demomen to deal with them quite easily, and from that exit, the ramp up from defensive spawn can be plugged with sticky bombs to significantly disrupt defensive movement.
If attacking C through A however, soldiers and demomen can reach the top floor with a single rocket or sticky bomb jump from the large concrete exit. Executing a well timed rocket jump from the explosion in the picture below provides ample thrust, and sticky bombs are of course even better. Remember to spam a few rounds at the top floor before jumping to clear out any resistance. Also remember that attacking demoman can reach the roof of B without touching the dirt, with just a single, well-timed sticky bomb jump from the left concrete tunnel exit.
Once points A and B are captured, all offensive engineers should put all their assets into building forward bases, preferably in the entrances from B, but it can help to also have some presence from A so you can flank sentry guns and the like. Teleporters are an absolute must, since they cut down the rather large transit time from spawn, cancelling out some of the defenders’ advantage.