hey so update I just encountered lil hunter for the first(and the 2nd time after that run) and she scared the shit out of me! I ran from her to do my usual boss thing of murdering everything and I forgot she had a jet pack and then well...I died without really knowing what happened expect for seeing some weird blue flames 0_0
As Misery said, Lil' Hunter is most definitely one of the toughest bosses in the game so don't feel frustration for losing to him often. I probably played 100 hours or more before I could beat this boss consistently and it still kills me sometimes anyway. That's because after player skill, a significant portion of the ability to beat this boss comes down to luck. Luck in terms of the stage layout, in terms of the weapons you have, and in terms of his random death pattern, which has killed me a million times.
Here are my tips for beating him:
1. Upon hitting stage 5-3, immediately run for cover.-You have about 15-20 seconds before Lil' Hunter shows up. You need to find a square, Arena-like dome where you can battle him uninterrupted until you kill him, before proceeding to the monsters on the rest of the level. A small square or cubby hole on the edge of a map is a useful place because you'll be safe from most the level's enemies and it will give you plenty of time to kill him (and his minions) without fear of being interrupted.
BEWARE, attempting to fight Lil' Hunter out in a huge, open area of the map is near-suicide. His direct ranged attacks happen so quickly that they are nearly impossible to dodge or react to, even with the Euphoria mutation that slows down bullets. Do not make the mistake of trying to dodge this boss' attacks, you need to avoid them completely and then hit him with everything you've got as soon as you see an opening.
Sometimes you will spawn in a nice cubby-hole Arena (with some decent cover spots) right at the start of the level, and those times are like blessings. Other times you will spawn in a giant square full of monsters. In those occasions, I have been known to run through 100 angry monsters with countless bullets flying left and right because it's better to take your chances dodging a bullet hell of enemies you aren't even attempting to kill in an attempt to find cover, than fighting Lil' Hunter out in the open.
2. You're going to need a bigger gun.-The more frontloaded the damage, the better the gun. I.e., you want to do as much damage to the little bastard in as small a time as physically possible. This means that Heavy Crossbow is superior to Crossbow, Auto-Crossbow is better than Heavy Crossbow, Heavy Auto-Crossbow is better than the former, Super Crossbow is a godsend, Super Bazooka is even better than that, and the Nuke Launcher takes the cake. The more damage you can pump out within one or two seconds, the better.
This is because Lil' Hunter usually never stays in one place for too long. Usually after a dozen seconds (or less), he will fly up into the air and change position again, so you need to be ready to unleash everything as soon as he lands.
3. Fight or Flight.-As I mentioned before, a halfway approach to Lil' Hunter just won't do.
You either need to be unleashing everything on him like an insane Rambo (this is ironically why Steroids is one of the best characters against him because he can unleash an endless hail of attacks, theoretically having the highest sustained DPS in the game). With Steroids I've killed this little monster within seconds (actually Steroids also seems to be one of the best characters against The Throne for the same reason. Given the right setup the conclusion of that battle happens more quickly than a teenager with PE disorder). However, the best character against Lil' Hunter in the game will most likely be your boy Y.Z., especially with his Throne Butt upgrade, because unleashing 4 attacks for the price of one can kill the poor guy instantly (and yourself if you're not careful) if you aim it right.
OR
Hiding for dear life and killing as many of the police spawns as possible. As I said, you can not take a middle-strategy with Lil' Hunter, casually killing other monsters while you wait for him to come into range and dodging his attacks out in the open. You either need to be going bezerk on him or hiding from him, heavily depending on the situation you're in.
4. My daddy always said walk softly...-Powerful melee weapons are extremely powerful against Lil' Hunter. Not only for the aforementioned reason you've already learned (they reflect his own bullets back at him), but clubs and axes are the best way to dispatch of his endless suppy of IDPD as well. The best way to kill his minions is to wait at the portals right as they spawn, then swing at the perfect time, killing them just as they come out (before they even have a chance to react). It's a little hard to get the timing down, but once you do it a single time, you should be able to do it every time. The nice thing about the IDPD is that they seem to drop health quite often (but never ammo for some reason), so even if things are going badly against Lil' Hunter, a health pack or two from his minions can actually be the boost you need to finish him off.
However, don't just use Melee weapons against his buddies, if the situation is right, charge in and smack him to death as well. The blue flame he spawns when he lands can be easily batted out of the way with a good swing, and then you're free to wail on him (usually until he dies), reflecting his attacks back at him (especially the aoe 'bouncer' attack) until he succumbs to the pain.
5. Run like hell.After you kill him, run for dear life. I've died to that death spiral more times than I can count. Technically, nowhere is safe. I've ever hidden in a long tunnel miles away from where the battle took place only to have his angry corpse fly into the tiny tunnel opening and chase me all the way down to the end before promptly exploding and ending my run. It's extremely frustrating. The best advice is to just to make as much distance between him and yourself as you can, and even that won't always save you.
Useful mutations: Scarier Face (less life on an already low hp bar), Euphoria (gives you that extra second to get behind cover), Hammerhead (make your own cover), Long Arms (makes killing and kiting him with melee weapons much easier), and most importantly
Boiling Veins because it means both his fire attack and his death explosion won't bring you below 4 hp.
1 is there a good reason to use the laser pistol at all? in the early game were it should be useful I T'Would 100 percent rather use the other weapons and in the later game for me the energy weapons are usually lightning and plasma weapons and very rarely a laser rifle so I don't whant to use it there either?
Laser weapons are vastly more useful with the Laser Brain mutation. This mutation literally makes some laser weapons TWICE as effective (such as the beam melee weapons, which it causes to swing
twice per attack). Laser weapons are also probably the most advanced to use because of rapid ammo consumption and because of some of the funky mechanics they have in general.
Generally, if you're going to use laser weapons I find that Fish is the best character to do it with. That's because Fish gets 20% more ammo than anybody else, and this even includes the ammo you glean from mutations (such as Lucky Shot). Fish with Laser Brain and Lucky Shot is pretty deadly because even the weaker laser weapons become sustainable and the more powerful ones are scary disgusting.
Fish with his Ultra Mutation 'Gun Warrant' (no ammo consumption for the first 7 seconds of a level), along with the 'Trigger Fingers' mutation, and a Super Plasma Cannon is an absolutely unfairly broken strategy, and shouldn't be tried at home.
So to answer your question: Don't use the laser pistol (or rifle) unless you're running Laser Brain, using Fish, or have no better alternatives.