The halo 3 bubble shield is an extremely versatile piece of equipment that can provide you with instant cover and allows room for a lot of strategy. It can be a real lifesaver and the difference between a win and a loss.
The most important thing to remember is that the bubble shield will deflect all enemy fire, grenades and projectiles. However, enemies can walk right into it, vehicles can storm right through it and enemy equipment can pass into it as well.
If you have a energy sword/gravity hammer, then you are golden. Have your secondary gun equipped and deploy the bubble shield, as your enemy is charging into your shield quickly switch to your hammer/sword and lunge at them. The reason why I recommend the energy sword and the gravity hammer is because they have a lunge and you can be on the outer edge of the shield still protected and lunge out at them if they try to back off once they see your newly switched weapon.
One tactic I like to use with the bubble shield can be an amazingly effective fight stopper if you are losing - On maps like construct with narrow hallways you can sandwich the bubble shield in between the two walls, deploy the bubble shield, step outside of it and throw a frag grenade at the foot of the shield and watch your enemy charge right through eager to get the kill. If the explosion doesn't kill him, your next BR headshot will.
If you have the power drain it is AMAZING for countering bubble shields. If your opponent is just camping inside a bubble shield with a power weapon, deploy the power drain in there. He will immediately lose his shields and from here if he stays inside he will not recover his shields, the explosion from the drain will take down the bubble shield and you can finish him off with a clean battle rifle shot. If he does run out of the shield once again you can finish him off with a clean battle rifle shot.
The bubble shield is also very useful against that annoying guy that always rushes rockets every game. This is really only effective at short range but the second he shoots at you deploy the shield and the rocket will bounce back in the direction it was fired from. This is a great way to not only force a suicide but also acquire rockets for your team and score a few quick kills.
The bubble shield is extremely effective in oddball games. Simply deploy one and camp inside for a guaranteed 15 second gain. If anyone comes in, you know what to do. When you sense the shield is about to run out, quickly run and crouch around a corner. The shield will still protect you from shots for the next second or two allowing you to get a clean getaway and then you can smack your opponents once again as they come running in looking for you.
The bubble shield can come in handy on neutral assault - has the enemy armed the bomb? Deploying the shield around it and camping inside with a power weapon all but guarantees a disarm.
One other neat trick is if you have the sniper you can align a headshot on a person camping in the bubble shield with the sword/shotgun and pull the trigger the second it comes down.
There are lots more uses for the bubble shield than I can possibly list here - like I said it is an extremely versatile piece of equipment. Try some of these out and work the bubble shield into your game play and you're one step closer to becoming a pro.
Halo 3 Bubble Shield Tips
Regenerator
The main problem and huge drawback is it is like a green glowing arrow pointing right at you that says "I'm over here". It will immediately give your location away to any enemy snipers and if they headshot you, you're regenerator is going to prove pretty useless. Unless they are complete garbage and haven't read my article on sniping they can get in 2 body shots before you have time to regenerate your shield completely. Other potential 1 hit kill weapons like the shotgun, sword, rockets ect. will take you out too. You can't regenerate anything if you're already dead. Also, it will do you no good against a needler. Once there's enough needles in you you're going to explode and the regenerator doesn't pick them out of your body for you.
Apart from that it is an amazingly effective piece of equipment. The regenerator is especially effective in team slayer/BR games. How many times have you been on opposite ends of the pit or a hallway on construct just BRing each other? Well if your side has a regenerator helping out then the enemies are sure to lose unless they retreat. I can safely say that any moron can take a 2v1 with the BR if the opponents are out in the open and you're just chilling in the regenerator.
In team slayer games when paired with the bubble shield it provides cover you can't get anywhere else. No shots can get through and your shields will be up before anyone manages to charge through. Go out, fight them, take cover when you need to.
If you are fighting an opponet in the regenerator WITHOUT a power weapon you should always meele and continue meeleing until your opponet dies. It does actual damage that doesnt just immediatly replenish. Dont even waste your time shooting with AR or BR because your not going to kill anything. Plasma grenades are also effective here.
Power Drain
Do you have an enemy just chilling in the bubble shield with the shotgun or sword? Throw one of these in there with him and you've got the kill for sure. He has one of two options from this point: Wait inside the bubble shield until it expires with the power drain and not bring his health back up, or coming out without any health and getting 1 shotted.
The power drain disables enemy vehicles for around 6 seconds. During this time the warthog gunner and the banshee pilot can still fire are you, however. Duck around a corner and take cover and throw one down just as the warthog comes speeding by looking for the kill. From here you can simply toss a grenade or two into the mix and that's an easy double kill for you. Banshee flying too low? Surprise him by throwing one of these at him! It will not only take down his shields completely but also bound the pilot to the ground for the period of 6 seconds. If he's dumb enough to stay inside, throw a grenade at him. If he isn't, the battle rifle will take care of him.
The power drain will completely consume a players shields - even if he has the overshield. This makes it extremely effective in social games like VIP and Juggernaut.
Another good use of the power drainer is putting up a barrier between you and your opponent, especially on maps with narrow hallways. The enemy probably wont be retarded enough to run right through it, and then you can go duck for cover, recharge your shields and get ready for the encounter.
Although the power drainer is handy in many situations, its most effective use is in neutral assault. Arm the bomb, throw a power drainer on top of the bomb, and stand back with a BR. They can either run up and try to disarm it and then get one shotted, or waste like 7-8 seconds killing you at which time they wont have enough time left to disarm the bomb.