Life-Model Decoy

"So much could go wrong." "Ultron, yes, I know. But this is not A.I. A.I. is banned and that's good; this is mimicry of human behavior." "But still, this can be used as a weapon. Is that the idea?" "No, absolutely not!"

- Leo Fitz and Holden Radcliffe

The Life-Model Decoys, or L.M.D.s, are androids designed to replicate every feature of a living person. They were originally designed by S.H.I.E.L.D. to be distractions and life-saving substitutes of their agents.

Original Program
"You have reached the Life-Model Decoy of Tony Stark; please leave a message."

- Tony Stark

Agents Billy Koenig and Sam Koenig participated in the original Life-Model Decoy Program of S.H.I.E.L.D. as programmers and technicians. However, despite their efforts, they never achieved to create a fully functional android. The project was eventually abandoned by S.H.I.E.L.D.

Tony Stark was evidently aware of the project as he jokingly purported himself to be his own Life-Model Decoy, analogous to an answering machine, to Phil Coulson when he arrived at Stark Tower to collect Stark for the Avengers Initiative in light of the destruction of Project P.E.G.A.S.U.S.

Updated Program
Holden Radcliffe created a body for the artificial intelligence that served as his assistant, Aida, based on the old S.H.I.E.L.D. program, believing that it would prevent the deaths that Leo Fitz and Jemma Simmons, of whom he had grown fond, had to witness. Aida was programmed as a decoy target for S.H.I.E.L.D. agents.

Aida also created an L.M.D. of Agent Melinda May, which took the place of the real one, and Radcliffe also created an L.M.D. of himself, which was ultimately destroyed. Later, L.M.D.s of Phil Coulson, Jeffrey Mace, Alphonso Mackenzie and Leo Fitz were created by Aida too. They were all destroyed by Jemma Simmons, Daisy Johnson and L.M.D. Melinda May who rejoined S.H.I.E.L.D. But an army of L.M.D. of Daisy Johnson has been created. Fortunately, L.M.D. Melinda May selfs-destructs soon after, destroying the S.H.I.E.L.D.'s base with all L.M.D.s Daisy Johnson inside, leaving Aida as the only L.M.D. surviving. But she constructs a new L.M.D. body for Anton Ivanov, leader of Watchdogs.

Trivia

 * In the comics, Life-Model Decoys are androids used by S.H.I.E.L.D. to substitute their top agent Nick Fury, who would have often used the LMDs in his battle against HYDRA.