Lucas Santino is the main antagonist in Jagged Alliance.
When the healing properties of the Fallow Sap were discovered, he convinced Jack to let him set up his own lab on the opposite end of the island, claiming research would progress faster. Once established, he betrayed the Richards, killing the rest of the research team, destroying Brenda Richards' lab, and seizing control of Metavira and very nearly every Fallow Tree growing on the island, and began processing the sap himself, taking advantage of the sap's rarity to make a profit for himself.
- Lucas' forces consist almost entirely of red-shirt mercenaries flown onto Metavira from elsewhere, and numbers of them populate every sector of the island. Their training and equipment varies wildly.
- Uses a convoluted system of notes written in code and shorthand to communicate messages to his forces in the field. While this makes it difficult for the player to discern the content of the notes, many of Lucas' own mercs find the whole thing unnecessary and confusing.
- Gus Tarballs is revealed to have briefly worked for Lucas' forces on Metavira. He quickly realized what was happening however, and quit after a few short days.
- "...find out who he is. Then...kill him."
- "You've run out of luck... ...we'll meet in hell!"