Book/book series where the main character's mind is copied into different alien clones

Question

Published no later than the mid-nineties, this science fiction story follows a man (possibly named Daniel or David?) who has his consciousness copied into a clone body modified to be of an alien species (or it could've been a real alien body with its mind wiped?).

Each part/chapter/book of the story follows a different clone/alien as they do whatever they were sent to do (I don't recall the reason for this; espionage, I imagine?).

One of the last clones/aliens is reptilian.

At the end (?) of the story, all the clones meet up with the original (assumed human?) character in what I vaguely remember as a shadowy meeting room with a round table and harsh lighting (that might be too much The X-Files filtering through though).

I originally read this book in grade 3 or 4 in my school's library, so it may have been aimed at young adults, but I recall the book(s) having a fairly mature/dark feel (it was the nineties, after all. Everything had to be edgy).

Answer 1

This might be Jack Chalker's Four Lords of the Diamond series:

The Warden Diamond is a system of four planets, ruled by their own lords, collectively called "The Four Lords of the Diamond". Each planet of the Diamond has its own special "Warden Organism", a symbiotic microorganism that lives within the inhabitants of the planets. The organisms destroy their host when he or she leaves the Warden Diamond, making the planet system the ideal prison colony for the Confederacy, a massive space empire.

An android clone that successfully infiltrated a government facility on a central world and downloaded vital defense information, transmits the information to a source and is destroyed in the process. The Confederacy discovers and tracks the clone towards the Warden Diamond, whose four lords are cooperating with an alien race to plan a mutiny against the Confederacy.

The government sends its best agent to investigate. Through technological advances, the government duplicates the personality of the agent (who remains unnamed throughout the series) and implants "him" into four brain-dead host bodies. The four hosts are then sent to four different planets in the Warden system and have no choice but to fulfill their assignment of locating and defeating each of the Four Lords, delaying the expected alien invasion and finding out vital information on the infiltrators.