Thanos is a powerful and malevolent character from the Marvel Universe, first appearing in the Marvel Comics series "The Invincible Iron Man" in 1973. He is a powerful alien warlord from the planet Titan, and is one of the greatest threats faced by the Marvel Universe. Thanos' story begins on the planet Titan, where he was born as the son of Eternals A'Lars and Sui-San. From a young age, Thanos was obsessed with death and the pursuit of power, and he quickly rose through the ranks to become one of the most feared and respected figures in the Marvel Universe. As a result of his Eternal heritage, Thanos possesses a number of superhuman abilities, including strength, speed, agility, durability, and regenerative powers. He also has access to advanced technology, including a suit of armor that enhances his physical abilities and a number of powerful weapons, such as the Infinity Gauntlet. The Infinity Gauntlet is a powerful artifact that allows Thanos to manipulate time, space, and reality itself. With it, he is able to erase entire galaxies from existence, and has even been able to defeat some of the most powerful beings in the Marvel Universe. Throughout his long and storied career, Thanos has clashed with many of the Marvel Universe's greatest heroes, including the Avengers, the Guardians of the Galaxy, and the X-Men. Despite their best efforts, these heroes have often struggled to defeat Thanos, making him one of the most formidable and dangerous villains in the Marvel Universe.
Groot is a character in the Marvel Cinematic Universe (MFCU) who is also part of the Guardians of the Galaxy. Groot is an extraterrestrial being who belongs to the Flora colossus species, a race of arboreal humanoids capable of regenerating and controlling their own plant bodies. In the UCM films, Groot is portrayed as loyal and brave, yet innocent and sometimes childlike in nature. Groot has a very distinctive personality and his vocabulary is limited to the phrase "I am Groot", although other characters seem to be able to understand his meaning based on context and intonation. Groot possesses superhuman strength and stamina thanks to his wooden body, as well as the ability to regenerate and grow his limbs at will. He can also throw sharp spines and control the vegetation around him. Throughout the UCM films, Groot plays an important role in the fight against the forces of evil, even sacrificing himself to save his friends on one occasion. After his sacrifice, a new Groot is born from a branch, meaning the character is essentially immortal.