Battle Suit

In Quake 3, the Battle Suit is a Powerup that makes it impossible for the user to be harmed by splash damage, and it also absorbs a fair amount of damage, lasting 30 seconds; it cuts in half all incoming damage and allows the bearer to enter lava and slime without being harmed. Initially spawns after 55 seconds to 1 minute mark depending on the map and respawns in three minutes after picked up. When a player has it, a golden glow surrounds him.

In Quake Live, Battle Suit is modified to protect the bearer from 25% of any incoming damage, and absorbs full self/splash damage.

Strategies

 * With a Battle Suit, you are a killing machine! Since splash damage doesn't affect you, use Rocket Jump or Grenade Jump to move around. You can also get close and personal with the Rocket Launcher without worrying about self-splash damage. So don't worry if somebody suddenly appears in front of you. Just remember that their weapons can still harm you, so don't think you're invincible.
 * Battle Suit can be used to reach the places you once can't with Rocket Jumps safely or walking over lava. Q3DM15 has both of these examples for players to demonstrate. Also it's great comfort to confront railgunners with relative safety compared to other players who don't have it. At long range combat, surely one can become hard to budge with it.
 * When you have Battle Suit, abuse grenade or rocket jumps to reach high places to keep yourself a safe position to snipe or lunge forward behind cover. If you abuse being airborne that'd be a distinct disadvantage between many foes even with the Battle Suit. Without airsteering properly, being airborne at the open for prolonged moments simply asking to get shot down in a crowded match. While versing against one foe at a time you can be bold enough to blast jump at the front of their very eyes to follow up with an airborne shot after you dodged or negated their shot.
 * Plasma Gun can be used to "activate" the Battle Suit to shield you from a rocket or BFG direct hit. When you see a single foe flaking a rocket or 'shooting stars' at your way in a narrow area with no chance to evade, look down and a give a short whirl to PG with single well paced shots. Generated splash damage will activate suit's blast shielding a short while and negate the damage from a direct shot entirely if you're lucky. Sadly same thing doesn't apply for hitscan weapons but a good maneveur to force a weapon switch when you're desperate.
 * As long as you have the suit, you don't have to worry about splash damage as much. Still you should evade sure hit projectiles by faking movement and bait shots by momentarily crouching. If you have a sense or some premonition at dodging shots, positioning low or infront of walls won't possess a big disadvantage with Battle Suit. Jumping around non-stop at the face of explosive projectiles, may initiate an unintended launch sequence where you can't retaliate accurately by being airbone.
 * Direct hit from explosive weapons can still harm Battle Suit users, but the Battle Suit user can spam explosives in tight quarters. If possible try to maintain a reasonable distance from Battle Suit user and pressure them with Rocket Launcher from below ledges or behind cover first to air juggle them. Try to retaliate with some other powerful hitscan weapon like Lightning Gun or Shotgun after they're airborne.
 * Battle Suit carrier can be slowed down by smartly shot Grenade Launcher at enclosed spaces or some airjuggling tricks at the open can waste their time. If possible lure Battle Suit carrier to bounce pads where you can retaliate with Lightning Gun, Shotgun or repel them backwards with Rocket Launcher. Grenades still an obstruct for them as collision still hurts but due to their blast shield, setting a grenade off with a rocket or a non-direct hit only gonna toss them around.
 * If you see somebody with a Battle Suit from long distance, take out a powerful and quick projectile weapon, such as the Plasma Gun or Railgun and use it against him. His suit only gives him little protection against non-splash direct and hitscan damage. Try to predict his movements if possible, then blow him away. Better if you can ambush them at the important pickups placed at high floors or ledges.
 * Railgun is a valuable weapon for Battle Suit carrier, not many weapons can answer quick enough to long distances and damage mitigation provided by suit increases survivability to hold important corridors. However waiting on a single position just to tag someone would only waste the precious time that you have. Also people can simply take cover to waste your time if you abuse it at the open. Battle Suit carrier have to seek hotly contested areas created by the cross paths between highly desired weapons and items, then position to have a sight upon them.
 * If Battle Suit carrier gets armor stacks like Heavy Armor their damage absorb rate will ramp up to 84% for a few shots they can incur. That means a railshot or rocket direct hit will only deal a mere 16 damage to their hitpoints, and just to burn their armor down you may need a second direct hit. Dealing a strong burst is important at the first sight.
 * Chances are, you can not prevent Battle Suit carrier to gather armor stacks but you can put a dent to their seemingly unstoppable force by timing Megahealth or Personal Medkit considering their long respawn time. If they can not heal on demand or amplify their effective health via over buffs, they'd be shuffling between armor spawns only along the time period. If they're already stocked up in health at recent minute, care to sweep lower grade armor spawns from their sight at least.
 * Battle Suit carrier will eventually visit health pickups after they went through chokes and follow a high route to be safe. Getting a drop on them with Shotgun or Railgun, can greatly hurt or harass them enough to delay their restocking. Getting a higher sightline near such chokepoints would allow a smart player to fend the Battle Suit bearer off to a bigger mayhem while you can track his trail to the nearest health pickup from high position with ease.
 * When you need to escape away from Battle Suit carrier, try to deny any health bubble you see on your way by dealing a slight splash damage to yourself even when you're at full health. That ensures if he gives you a chase he'd need to retreat just to heal.
 * In any team game other than FFA, try to coordinate with your teammates and gang up on the Battle Suit user and his powerup will not do very well. This especially applies if they're the high stacker Megahealth and Heavy Armor bearer of their team also.
 * The Battle Suit will also keep the player from drowning and suffering fall damage, besides environmental hazards like lava and acid. The Battle Suit does NOT protect you from the Void and/or The Fog of Death. The Battle Suit wearer is also invulnerable to the Kamikaze in Team Arena, but blast can push Battle Suit wearers up to a wall and sometimes to Void and/or The Fog of Death behind them.
 * In Quake Live it's mandatory to stack armor before acquiring Battle Suit because even if it reduces damage by 25%, this is merely enough to face newly respawned players before they get a drop on you. Armor stacked Suit bearer in QL reaches 75% damage mitigation which is not forceful but still a powerful value to give survival. In classic Arena, Battle Suit allows you to dominate certain goodies for a power shift because it gave close enough damage mitigation to rival an armor stacked player.