Booze-Based Buff: Inverted; depending on whether he's drunk or sober, Larry's skills in JA2 change, along with his portrait and voice, but his stats are worse when drunk. This also affect his working relationship, he gets friendly with AIM when drunk but cannot tolerate the MERC soldiers while in sobriety he gets along fine with the two worst mercenaries in the roster but the AIM Mercs hates working with a sober Larry.
Dysfunctional Family - The Roachburns DO NOT get along with one another, Larry at least is cared for by Megan. His brother and father outright hate him though.
I Need a Freaking Drink: When walking by rotting corpses being eaten by vultures, he remarks that "People wonder why I started doing drugs..."
Edward "Ears" Stockwell
Murray "Moses" Ebstern
Patrick "Screw" Phillips
Helmut "Grunty" Grunther
Bash Brothers: With Ivan and Igor. Putting the three of them together makes for a hell of a team, thanks to their complimentary abilities.
BFG: Grunty has the heavy weapons specialty, making him very effective with grenade launchers, missiles, and mortars. Now, if he had the strength to carry those and the ammo....
Fluffy the Terrible: His opinion on the Crepitus, calling them "cuddly creatures" and musing on whether they can be tamed.
Ascended Fanboy - Turns out, he left AIM because he got movie deals in Japanese-made Westerns. He returns in Unfinished Business as a mercenary for MERC, still wanting a taste of gunning down bad guys Western-style.
Psycho for Hire - A lot more muted in Jagged Alliance 2, in which AIM slapped him and sent him off for counseling. They note he hasn't been himself...
Straight Gay - the bits of dialogue resulting from experimenting with the "handle" command in JA:DG suggest he prefers men.
Hurl E. Cutter
Annoying Patient - ...and severely hypochondriac with the absolute highest health rating possible (100).
Action Survivor: If you actually take him through the majority of the game and he lives.
Dirty Coward: He quits in the first game immediately after anyone dies, friend or enemy. He'll stick around in the second, though he's still pretty much soiling himself everytime the bullets fly.
Maj. Spike Scallion
Dr. Raffito "Raffi" Leevon
Back-Alley Doctor - not only his credentials, but also his skills and general sanity are all very questionable.
Cynthia "The Fox" Guzzman
Beware the Silly Ones: Fox's dialogue is laden with innuendo, and she has a whimsical, cheery personality at total odds with the violence around her. But she is absolutely deadly at close range, especially in room-to-room combat.
Combat Medic: An inexpensive and effective early game medic.
Guns Akimbo: High dexterity and gunsinging/ambidexterious traits make her one of the best dual-wielding mercs in the game.
Ms. Fanservice: Though not in-game, she's apparently notable for doing centerfolds for mercenary magazines, and is praised for her curves as much as for her skill with weapons and medicine.
Really Gets Around: Implied; she is apparently in a relationship with Wolf, she and Grizzly seem to have a thing, and she mentions dating Mike if she's the one to kill him in JA2.
Waif-Fu: Her high dexterity makes her utterly deadly with a knife in the first game. Less so in the sequel.
Genius Ditz - Between saying "like" in every sentence and missing every shot she ever fires, she's a master repairer- able to repair more points of gear per mission than Speck despite his higher mech score (due to a much higher dex).
Dysfunctional Family - The Roachburns DO NOT get along with one another, Megan at least cares for Larry.
Friendly Sniper: Cheerful, outgoing and articulate. Also, has maxed-out MRK and a history as an SAS sniper. She's one of the most stable possible teammates as well, only objecting to Tim "Numb" Sutton (mostly because he's just that good at pissing everyone off).
Improbable Aiming Skills: She's one of the few mercs able to manage hits on "impossible" targets (i.e. blanked out and prompting a "are you serious?" quote from the merc in question) Appropriately enough, her response is not a variation of "I can't hit that" but "Are you sure you want me to hit that target from here?" She's still not likely to hit the blanked out target, but she has a chance that others don't.
Col. Leon Roachburn
Bash Brothers - Very good friends with his war buddy Sam Garver, if he gets fired he will follow suit.
We Help the Helpless: Gus makes it clear that while he sells his considerable talents, he's interested in doing good with those skills. His answering machine even mentions that he's constantly out "righting wrongs."
Introduced in Jagged Alliance 2:
Carl "Reaper" Sheppards
Anti-Hero: While certainly a ruthless and dangerous man, Reaper admires the bravery of the Arulco rebels, and looks forward to ripping out Deidranna's soul.
Properly Paranoid: When hiring him, he makes it a point to demand that once his employment is terminated, he gets all paperwork related to the operation so he can destroy all record of working for you.
Stealth Expert - Paraphrasing his bio: "...that shrub, sand dune, snow drift or satellite dish could easily be this master of disguise. He has made it his business to blend into any kind of environment for any length of time." And it shows - he's a 100% camouflaged in all environments, regardless of what he's wearing.
Battle Couple: With Raven. Raider even suggests that he be paired up with Raven when being hired, and the A.I.M. dossier on them mentions they work extremely well as a team. They both get a major morale boost if on the same squad. The dossier also mentions that fears of nepotism aren't warranted, as they act strictly professional in the field.
Reasonable Authority Figure: In fact, he's got the best leadership in the entire game, coupled with the Squadleader skill, making him the ideal leader of any mercenary team. Being an ex-SWAT team commander, this makes sense.
Love Triangle: If Hitman's on the same squad. Oddly, she doesn't do anything - Hitman and Raider just argue and take a huge drop in morale.
New-Age Retro Hippie - His bio states he's a healer. Of course, he's good in artificial medication, too.
Poirot Speak - probably the second most prevalent one besides Ivan.
Consummate Professional: Treats this mission as a business venture rather than fighting for a cause. Also, he hates most the duo stoners Larry and Static due to them being seen as rather "infantile" and wonder how they get their job drunk and high.
No Blood for Phlebotinum: Worked a diamond mercenary/consultant and thus worked in protecting foreign resource interests. Dimitri hates him for that since that was what allowed Diedriana to oppress the nation into a dire straight of poverty.
Genius Bruiser: as the name implied, he is very strong. He is also one of the best mercs for repair, computers and lockpicking until you can afford specialists (and even then, still good). His primary weakness being speed.
The Ace: Of the low-cost starting mercs, she's one of the best all-rounders, especially with marksmanship. The decent leadership, the teaching skill, high wisdom, and solid physical stats complete her.
The Big Guy - Probably the best example in the whole Jagged Alliance. However, while his strength is tremendous, he's not agile on his feet and his dexterity is poor enough that he often misses with firearms. Find him a spot to set up with the heavy weapons, though....
Disc One Nuke - He's an extremely cheap starting mercenary who also has heavy weapons proficiency. In v1.13, one of his starting kits includes the M79 grenade launcher, and you can buy 40mm grenades right at the start from Bobby Ray's. Loading Grizzly with grenades and letting him put in some work is one of the most effective ways of staving off the infamous Drassen counterattack in v1.13.
Badass Bookworm - His AIM profile specifies that unlike most mercs on the roster, he learned all of his skills with explosives and machinery in a classroom. His answering machine also indicates that his "assignments" seem to often involve him doing lab work instead of combat.
Badass Preacher - His lines show that he is rather religious, and takes matters of life and death seriously.
You No Take Candle - Not as bad as some examples, but his command of English is...not perfect.
The Alcoholic: Not impaired like Larry, but is enough of a heavy drinker for Ivan to make a note of that whenever they walk through a field of corpses.
Badass Family: Nephew of Ivan Dolvich, so you know he's a badass. Part of his motivation is to become as good as his legendary uncle.
Bash Brothers: With Ivan and Grunty. Pairing Igor, Grunty, and Ivan on the same squad not only lets them very solidly complement each other with their respective skills, but gives them all a huge morale boost.
Friendly Sniper: Altogether a good-natured guy, but the Hunter trait he possesses (in 1.13) means he is a deadly marksman with a rifle note Rifle. Not assault rifle or sniper rifle, but bolt-action or semi-automatic, medium-to-long-range marksman rifles.
Genius Bruiser: Igor's base skills are not exceptional starting off, but his physical stats in general are great, and his high wisdom ensures that he learns very fast. In his own words, "I am from a family of quick learners!"
Beware the Nice Ones: Despite his cheeriness and idealistic disposition, he is deadly with a knife, and his high wisdom means he learns fast, especially when coupled with an expert teacher like Buns.
Magikarp Power: Has one of the highest wisdom stats in the game, meaning he will rapidly progress from his Wide-Eyed Idealist base to a hardened killing machine or your squad's Mr. Fixit if you train him in mechanical work. Have him regularly training people in medicine, and his leadership will shoot up like a rocket.
The Medic: Quite well versed as a doctor straight out of med school. His strong medical skills make him a good excellent medical teacher, with the added benefit that this will shoot his leadership up dramatically.
The Big Guy: Has the highest strength stat of the entire AIM roster. Coupled with his specialty at hand-to-hand combat, and Bull is your go-to guy when you need a face rearranged.
Blood Knight: known to be violent and aggressive and while he is tough as nails in combat he is also known for a lack of discipline. He's also eager to enter combat; the only times you'll get more than a short sentence out of him is when he either enters combat or after you've killed everyone.
Dumb Muscle: His marksmanship is pretty good, but otherwise the one area where he is best at it raw physical strength, and this is reflected in his fees: he's the cheapest non-MERC mercenary available. He also has only middling wisdom, so he's not going to become a master at much else unless you put a ton of work into him.
Hidden Depths: Married, with several kids. You'll only learn about this if Grizzly is on the team and Bull dies.
Meaningful Name: John Peters was actually a famous British mercenary who fought alongside Mike Hoare in the Congo in the 1960's.
The Quiet One: Played with. Bull is laconic, speaking in short, curt sentences usually, but he's still relatively loud when he does speak.
Frankie "Haywire" Gordon
Axe Crazy: He considers Vlad the Impaler to be his personal hero.
Groin Attack: For some reason, Razor seems to have a tendency to score these more than other mercs.
Insistent Terminology: He's not psychotic, he has a passion for his job. And he'll carve his initials into the chest of anyone who disagrees.
Knife Nut: His dominant skill. v1.13 also gives him bodybuilding, making him a good mule, and coupled with some impressive strength, it makes him your go-to guy from the M.E.R.C. roster when you need to go into close combat with a couple of machetes.
Magikarp Power: One of the rare cases where this applies despite having a pitiful wisdom stat. His combat skills are poor - even marksmanship is low - but his strength, agility, and dexterity are through the roof, comparable to the top-tier A.I.M. mercs. Get him early and keep him fighting or training, and he'll become an incredibly cheap but powerful soldier.
The Scrappy: In-universe. The list of mercs who Tim pisses off with his mere presence is impressively large. You know you're an asshole when Reaper hates you.
Jim "Cougar" Wallace
Only Sane Man - before Unfinished Business came along, he was the only professional mercenary among the crowd of cowards, civilians, psychiatric patients, mental defectives and other misfits that was the M.E.R.C. roster. The most expensive, too.
Military Brat - His father ran a military institute, and he follows the regs to the letter. In fact, he wouldn't be out of place in a World War II flick.
Ax-Crazy: Probably the only reason he joins you is that he always wanted to kill the queen's goons. He's the only RPC who will join you free of charge without you needing to do anything special to recruit him. All you need is a merc with good leadership to convince him, and he'll gleefully join.
Disc One Nuke: His starting gear includes a CAWS, which is a hilariously powerful shotgun. Since you can recruit him for free in Estoni, he can practically join your team before you've taken Drassen - assuming you're willing to trek that far south and evade the patrols on the roads to pick him up.
Large Ham: "I'm here! And I ate every bug on the way! There were many!"
Magikarp Power: The only problem with him is he is level 1 when you get him, if you manage to get him to level 4...
The Engineer: Boasts solid mechanical skills and good wisdom, with the "Engineer" skill on top of that.
Heart Is an Awesome Power: His only real special ability is his Engineer skill, which is relatively rare (Technican is much more common) unless you're talking high-priced mercs like Trevor. But Engineer gives some startlingly huge bonuses to the Robot's operation....
Roaring Rampage of Revenge - Having your family executed in front of you kind of makes that happen. Refuse his initial offer to hire him for a measly $50 a day, and he'll offer to join you for free just to have a part in killing Deidranna.
Trigger Happy: The Psycho trait he bears means he has a thing for going off with anything with an automatic setting. Give him a semi-automatic and keep him out of the line of fire unless you want to waste a lot of bullets....
Arms Dealer: You'll initially encounter him selling explosives and explosive-related gear. With good leadership, he'll join up for a steadier paycheck putting explosives into your enemies.
Breeham "Shank" Druz
Heart Is an Awesome Power - He's a rather useless rebellious teenager, who happens to have practiced knife-throwing to impress his friends at parties. Guess what's the most effective way to stealthily kill somebody in this game?
Magikarp Power: Unlike most recruitable characters, Shank's stats are bottom-of-the-barrel low; even most M.E.R.C. employees have better. But his wisdom is good, and if you work on his strength, put him in some light armor, load him with throwing knives, and in v1.13, a full ghillie suit and night vision goggles, and he can be downright deadly.
Dr Vincent Beaumont
Made of Iron: Has absurdly high starting health, being a professional doctor.
Magikarp Power: Like most medics, his wisdom is sky high, so he learns fast. Get him early on and train him well, and he becomes a pretty impressive shooter.
Only Sane Man: He puts it rather succinctly if you talk with him out of combat: "Two words: Mental ward."
Lt. Conrad Gillit
Awesome, but Impractical - Great in everything... if he wasn't hideously expensive. He can be hired for relatively lower (3300$ per day instead of 5500) cost if you turn him down at first, but still have a decent leadership.
Boisterous Bruiser - He likes to boast if he kills something (especially crepitus), though in a humorous way.
Insufferable Genius - A solidly competent soldier, trainer and a leader who sees himself as nothing less than a celebrity.
More Dakka - He is an automatic weapons specialist.
Mugging the Monster: Try to talk to him for too long, and he'll decide it will be more fun to just shoot you. You'll usually have a half-dozen heavily-armed badasses standing behind you who just cleared out the rest of the military academy of equally well-armed soldiers....
Igmus "Iggy" Palkov
The Atoner - He is recruited by Dedrianna, and regrets it.
Mr. Exposition: Will, snarkily, give background on locations if she is sent there after they have been liberated.
Magikarp Power - Her marksmanship is abysmal, but her wisdom is sky-high. This combined with time, patience and her expert-level Teaching specialty means she has the potential to be both a competent gunner and the absolute #1 militia trainer in the game.
It Has Been an Honor: Most mercs and other recruitable characters react poorly to seeing a horde of enemy troops. Dimitri? "Good! We will all die together!"