Search and Destroy (SD)

Anyone who's played Counter-strike will be familiar with the premise of sSearch and destroy, in which one team is responsible for defending objectives, and another team is tasked with destroying them. The gameplay is similar to Retrieval, except that there are always two objectives, the destruction of either of which will end the round.

The catch is that the objectives cannot be destroyed by regular weapons, but must instead be demolished with explosives. Every player on the offensive team is assumed to be packing explosives, which take just a few seconds to lay on an objective. On the other hand, every defending player is capable of defusing explosives, but this operation requires a much greater length of time than does the actual explosive-laying. If either team's soldiers are killed off completely, the other team wins automatically.

Tips

• Using your ears becomes more and more important as the number of players in the game diminishes. If you're one of only a few remaining players on your side, you'll be able to compare footsteps with your compass to tell whether or not you're hearing an enemy. Also of note are the sounds made by laying and disarming explosives; if you're defending an objective, and begin to hear someone laying explosives, you're probably already too late to prevent them from completing the task, but you may be able to garner a kill with a blind grenade toss. If you're on offense, and have laid explosives, then hide somewhere out of sight and wait until you hear someone attempting to defuse the bomb. Defusing explosives takes around 15 seconds, so you'll have plenty of time to turn the corner and kill off the enemy.
• Of course, if you're attempting to defuse a bomb, you should always assume that someone is hiding nearby. If you're on your own, try hitting the use button very rapidly while standing over the bomb, then ducking out of the way to see if any foes come into view after they hear you. Bombs take quite a while to detonate, and won't detonate if someone is attempting to defuse them, so you should have enough time for a gambit like this. Otherwise, grenades are always useful when attempting to flush out a hidden enemy, although the hardcore players will remain hidden no matter what, unless they figure to take lethal damage from your grenade.
• As a round proceeds, the chance of a frontal assault succeeding grows stronger, assuming each side has suffered a similar amount of attrition. If you can group all of your soldiers together and rush one of the objectives, you'll likely encounter only half of the defenders, and thus at least one of you should have a chance to plant your dynamite.
• Whether you're laying or defusing a bomb, your chances of survival are much improved when you have one or two teammates around to watch your back. This becomes infinitely more important as the number of surviving players approaches zero; in a two-on-two match, the team that sticks together will almost always wind up winning.

Behind Enemy Lines (BEL)

Behind Enemy Lines is a twist on the standard Team Deathmatch format, in which the Allied team is consistently outnumbered by the Axis players. The Axis side will usually have around two and a half times the number of players on it as the Allies. The Allies do gain the benefit of automatic health regeneration, and gain one point for every ten seconds that they manage to remain alive.

To make things a bit more interesting, though, the Axis also possesses the ability to spot Allied players on their compass. If an Allied player pauses or remains in the same place for too long, a blue question mark will appear on the HUD of every Axis player, thus ensuring that your position will soon be under assault by superior numbers. The final complication, and what makes Behind Enemy Lines so interesting, is that Axis players who kill an Allied player immediately switch sides and become Allies themselves, while their dead target becomes an Axis soldier. Chaos typically ensues.

Tips

• As an Allied player, you should either attempt to stay mobile to avoid appearing on enemy compasses, or attempt to find a killer spot where you're impervious to enemy fire. There are few enough of the latter, but keep in mind that the question mark on a compass doesn't indicate the height of the signal. Thus, on maps with buildings (we're looking at you, mp_pavlov), you can rest assured that the enemy won't be able to get more than an idea of which structure you're hiding inside. If you remain in one place long enough, however, you can expect a hail of grenades to come your way as your conquests respawn.
• As with the other team-based multiplayer games, teamwork is important, especially so for the beleaguered Allies. Since targets are difficult to come by for Axis players, they often rove around levels individually, which can make them easy pickings for pairs or even three Allied players moving together.