Shotgun (Q3)

In Quake 3 Arena, the Shotgun, or "SG", fires 11 pellets in a cone-shape. Due to the erratic spread of the pellets, it should only be used at very close range. If all of the pellets hit, the Shotgun can kill a healthy, unarmored target in one shot at point-blank range. Shotgun is a hitscan weapon with mediocre spread and a long reload, generally preferred to keep foes at bay.

Strategies

 * Since the Shotgun is only effective at very close range, you'll have to get really close to your target to kill him. Try to ambush them so that you'll be able to get a clear shot in without getting attacked. There's a significant delay between shots, almost as long as the Railgun's, so try not to miss.
 * Especially when stepping through a gate, Shotguns can surprise your foes making them lose a fair chunk of health, even if you fail to land a good amount of pellets because of random spread or distance. Twitch shots from mid-air can be a rewarding strategy when you can't estimate the distance between yourself and the opponent at the first look.
 * Hiding near corners and leaping out when somebody comes by is a good way to catch your target off-guard. Remember that you have one chance to kill them. If you screw it up, the target will be away from you and firing before you get another chance to hit back. Depending on how much damage you did, you can fire again and hope a few more pellets will hit them.
 * For easy frags you may roam for checking on health orbs constantly and hunt down any low health player you may stumble upon. If possible, try to cut a wounded opponent's path when they're on their way of healing and stay silent near gates and under catwalks.
 * Seek slight height advantages like ramps, porches or stairs so you can rain pellets down upon foes. Sidejumps when using the Shotgun is a nice tactic to utilize the pellet spread. Bouncepads or peeking from a higher floor will give you enough distance to raindown pellets at what's below.
 * If you're feeling in the mood for pissing people off, aim at players who are hovering from bounce pads. Shotgun may be generally weak against mid-air targets but bouncepads make your foes a sitting duck unless they steer away to evade, or check what's above by pre-firing before they elevate. Even if you're at a ground level, a crouched Shotgun shot against opponents who take the bouncepad or try to rocket jump will greatly disrupt their air momentum.
 * The Shotgun is a great finisher weapon for close quarters or foes taking cover behind a corner. Once you have weakened them with a rapid weapon like the Machine Gun or Lightning Gun, cease fire then draw the Shotgun quick and do the finishing touch. Leading the shot is not necessary unless you're up close and personal with the foe, so try to run to their sides until you're up to them for the finisher shot.
 * When fighting against a Shotgunner; momentarily crouching at medium distance may allow you to evade quite a few random pellets. Pulling the same tactic at close quarters generally makes you a sitting duck. Run to the Shotgun bearer's sides first if you're too close, and step away and open fire at them before you try to crouch for evade. Most of the time Shotgunners will abuse side jumps. Try to crouch-momentarily and mirror their side direction but try to maintain the distance between so less pellets will hit you unless they do a well put twitch shot.
 * The Shotgun is effective at mid-range as well. You may miss by about 5 pellets, but you'll still deal around 40-50 damage per shot. Its close up meatshot deals slightly more than most damage-burst weapons in your arsenal. 11 pellets sprayed with each shot with a rather medium spread radius and almost infinite range. That makes long distance shots throughly based upon luck but still useful.
 * Seeing as one pellet does 10 damage and most players have under 100 health in a crowded map, you can clear the weak foes at long range in a chaotic match. Just aim at the general direction of a heated fight and fire away at long range. Only use this tactic if you have plenty of ammo. Never use your last bits of shells for poking your opponents from far away, save it for close quarters where one shot equals one kill.
 * In Quake Live, the Shotgun is modified to spray more pellets at a larger area, but has a very limited range (of 1500 units, twice as much the Lightning Gun's range) and reduced damage per pellet. QL's Shotgun fires 3 different rings of pellet spread in one shot and have 42%~ larger spread radius. The outer ring pattern consists of 10 pellets with middle and inner rings spraying five pellets each, a total sum of 20 pellets sprayed with each shot. Their damage per pellet is also halved down to 5 damage. That trade off makes the Shotgun more versatile at holding large gates with increased spread radius and higher pellet density, but limited range makes it suffer at wide open areas without cover.
 * When you are noticed to carry a Shotgun and chase, foes will open suppression fire to fend you away. A smart grenade barrage can wash you away from any position. The same holds true for the Railgun if your footsteps alert foes below, or if you happen to go personal with a Lightning Gun carrier.
 * Shotguns can be a great counter weapon against Rocket Launchers. As RL user tries to get closer to land better hits, buckshots will riddle the foe with pellets even more with every step they take. As they get closer and jump, just crouch and fire away to disrupt their mid-air momentum. If the RL user is a good player this tactic may not work very well, since they can keep a distance and get clear direct hits. Still, a pellet barrage will discourage them from trying some close up weapon combos.
 * If you primarily use your Rocket Launcher, switch to the Shotgun at close range and gates to avoid taking splash damage upon a surprise attack. That just doesn't help you in conserving ammo but also prevent you from pre-fire and suffer reloading at enclosed spaces after missing a rocket. At the open areas after an airjuggling rocket to make opponent airborne, you can do a follow-up with a crouched Shotgun spray as well.
 * A Plasma Gun can be used to cover your approach against unaware opponents from medium range and a follow-up buckshot barrage can be used to punish anyone who tries to dodge the large array plasma beats. For this combo to work, opponent must be unaware at mid-range and PG must be combinated with the Shotgun for a finisher shot. Of course when pitted against more than one opponent at a time, you may get cluster fired if you got in too close.
 * If an enemy has the Shotgun, keep distance from them and open fire. The Shotgun is better than you might expect at medium-close range, although other weapons are often preferred. At close, use automatic weapons to cause them to panic or your own Shotgun.
 * Haste works great with the Shotgun, as it allows getting another shot in quickly if you miss the first time. Moving faster means getting close to the enemy is easier.

Advantages

 * Devastating at close-medium range.
 * Common in most maps with more than one spawns.
 * Large random spread that is great at sweeping gates and pre-firing.
 * Hitscan, thanks to large spread no leading required unless too close.
 * Good finisher weapon for foes looking for a recovery or weakened recently.
 * Easy to use on the move or airborne.
 * Opens a breathing space in crowded combats.
 * 3-ring spread gives a longer effective reach in Quake Live.

Disadvantages

 * Slow rate of fire, missing will be punishable at close range.
 * Ineffective at longer ranges.
 * Random deviation of pellets cause slight misses at average combat range.
 * Takes a damage penalty in team-oriented TDM and CTF modes.
 * Quite ineffective against distant airborne targets.
 * Spamming at long ranges eventually gets you some unwanted attention.
 * Any sort of suppression fire gets you overwhelmed.
 * Reduced pellet damage in Quake Live.

Trivia

 * The Shotgun apparently has an laser sight underneath the barrel but it can never be used. This becomes more visible among the smoke when firing the Shotgun, but it's actually a thin layer of static imagery work embedded into the gun model.
 * Strangely, despite having two barrels and visibly ejecting two shells with each shot, the Shotgun only consumes one shell when it's fired. That only points at its shells being double stacked standards and count as one shot each.
 * The Shotgun is apparently a pump-action double barrel instead of a break-action. That makes it pretty close with its Q2 counterpart.