Much like Osamu Tezuka, Jac was a total workaholic: he created well over a hundred books and dozens of characters, his works spanned almost every possible genre (including western, adventure, fairy tales, sci-fi, pulp detective stories, adaptations of famous novels and even pornography) and never stopped drawing up to the day of his demise. In his youth he was influenced by E.C. Segar (creator of Popeye)'s comics among others, and later he himself influenced other creators such as Francisco Ibáñez.
His most famous creation is Cocco Bill, a hot-tempered but loyal and righteous cowboy who rides his talking horse Trottalemme (Slowtrot) and only drinks chamomile tea. Cocco Bill starred in a big number of comic books but also in a series of animated ads from The '60s and two seasons of an animated series from 2001 that lasted 104 episodes. His style is identifiable by his characters having big noses and feet, stretchy limbs, strange anatomies, but especially by the fact that he fills every empty spot in the page with stuff of every kind. Expect to see pencils, salami and feet jutting from the ground, googly-eyed worms and butterflies watching the characters, combs, dice and flasks scattered everywhere, just to name a few.
His life and works provide examples of:
- Affectionate Parody: A few of his characters were parodies of well-known properties, such as Zorry Kid (Zorro), Mandrago (Mandrake) or L'onorevole Tarzan (Tarzan, duh). Pecor Bill, a cowboy who rides a sheep, is a parody of Pecos Bill but In Name Only.
- Animated Adaptation: As mentioned above, Cocco Bill received one that spanned over 100 episodes. Zorry Kid was supposed to have one too, but only a short trailer was ever produced.
- Author Filibuster: Averted and defied! He worked for both conservative and left-wing publications, and still managed to piss both off for writing/drawing something he wasn't supposed to. He also defined himself as a "center-wing extremist" and made fun of the fact that all of his three names were linked with dictators (Benito Mussolini, Francisco Franco and Giuseppe (Joseph) Stalin).
- Big, Thin, Short Trio: The 3 P's, a group of three inseparable friends who share the initial of their names and were among Jac's earliest creations. They are Pippo (pictured above) Pertica and Palla. Pippo is the hot-blooded, short one and the leader, Pertica the tall, brainy and rational one, and Palla the fat, shy and easily scared one.
- Bloodless Carnage: In his stories Cocco Bill murdered hundreds of bandits, natives and other bad guys, and someone even complained about it. But it's all extremely cartoonish and surreal, with no blood in sight and the guys being shot making backflips or directly landing into open coffins!
- Breaking the Fourth Wall: Very common, especially in his more comedic stories.
- Bunny-Ears Lawyer: By all accounts, Jac was both an incredibly talented artist and an incredibly weird person. Just one example: he put outside his house the sign "Beware of the Camel" and every now and then he made strange noises to mantain the joke!
- Canine Companion: Tom, the little runt that always follows the 3P's. Also Cip the detective's basset hound Kilometro.
- Catchphrase: Among others, Cocco Bill's "Mondo pistola!", Cip l'arcipoliziotto's "Lo supponevo!" ("I assumed it!") and his assistant Gallina's "Maestro, che faccio? Sparo?" ("What do I do, master? Am I going to shoot?").
- Hardboiled Detective: Homaged and parodied in the Joe Balordo stories.
- Ironic Nickname: In his youth he was known as "Lisca di pesce" ("Fishbone") because he was extremely thin, so he started signing his works with "Jac" and a drawn fishbone beside the name. Later on he was not so thin anymore, but mantained the nickname and sometimes remarked on it.
- Living Shadow: Zagar, the arch-enemy of Cip the detective and a Master of Disguise, is probably one of these. Sure, it could just be a Spy Catsuit, but it covers all of his body (only eyes, a manic grin, gloves and a panama hat are seen), he's never seen outside of it, he puts his disguises on top of it and sometimes he apparently morphed into other shapes.
- Never Mess with Granny: La signora Carlomagno ("Mrs. Charlemagne"), who is in her 80s or more but practices lots of sports, always managing to break bones whenever she shakes hands with someone, possibly Immune to Bullets and possesses a mean Megaton Punch. Oddly enough the only other character that can compete with her is another old woman, Granny Spaccabue.
- Painting the Medium: One of the many methods that Jac used to make his readers laugh. One example is Bernardo, Zorry Kid's manservant based upon Zorro's mute manservant. Bernardo is not actually mute, but illiterate: his balloons never have any words in them, because he never learned how to write!
- Phrase Catcher: A bizarre example since it's not directed to a person, but an entire state. Zorry Kid's adventures are based in California, and every time the state is mentioned it's invariably referred to as "La cosa, la California".
- Prince and Pauper: One early story of his (dated to the early Forties) featured an evil duke who after shaving his moustache became the exact copy of the king and plotted to dethrone and replace him. Things are further complicated by the arrival of another Identical Stranger, a poor farmer, with whom the king trades place. Only a few pages of the story, however, have been preserved.
- Recurring Character: Since Cocco Bill didn't have any arch-nemesis in his stories (as opposed to, say, Zorry Kid, who had California's governor Don Pedro Magnapoco), they decided for the Animated Adaptation to make some recurring characters (evil industrialist Bunz Barabarunz and the seven twin Kuknass Brothers) responsible for most bad things that happened to him.
- Repetitive Name: One of his gags, with characters named "Alonzo Alonzo detto Alonzo" or "Giuseppe Giuseppe detto Giuseppe".
- Sapient Steed: Trottalemme, as stated above, but also Zorry Kid's masked horse Saratoga (who is, according to Jac, an accountant when not fighting crime!).
- Spirit Advisor: An unusual case in the Jak Mandolino stories, because the "spirit"'s advice is used for bad deeds, and because it is always doomed to fail. Jak is a lowly hoodlum who aspires to become a master criminal, and to reach that goal he follows the advice of the little devil/imp Pop Corn. Since these were comic book stories for kids, Jak's bad luck and Pop Corn's ineptness make sure that the crimes are never succesful and Jak remains a loser forever.
- Sublime Rhyme: The names of his characters often rhymed with what they were, some examples: Raimondo il Vagabondo (R. the Tramp), Elviro il Vampiro (E. the Vampire), Battista l'Ingenuo Fascista (B. the Naive Fascist), Mandrago il Mago (M. the Magician) and so on.
- The Teetotaler: Cocco Bill's favorite drink is chamomile tea, he drinks it by the liter, but alcohol has harmful effects on him! As often happens in westerns, even comical ones, he also killed some people who made fun of him for this.
- What Could Have Been: Jacovitti already drew three comic book versions of Pinocchio and was working on a fourth one, tentatively named "Pinocchio di Falco" (something like "Hawk-Eye Pinocchio"). It was meant to be Pinocchio In The Wild Old West, with the titular character as a native, the Fox and the Cat as Mexican bandits and so on. Unfortunately he passed away after making only a few sketches.
- Xtreme Kool Letterz: He changed his surname from Iacovitti to Jacovitti just because.