Name of Sci-Fi/ Horror Where a young man is possessed By "Aliens"?

Question

its a weird movie from like 78 the guy is tranformed by aliens and can shoot photons out of his arm, but he does not like it

Answer 1

Laserblast (1978)
Alien creatures kill a mutated alien creature in the California desert. Its remains, and the high-tech laser gun and power source accidentally left behind, are found by an ostracized teenager. However, the power source causes the teenager to mutate, too, and he goes on a murderous rampage. Eventually, the first aliens return to kill him as well, and then forget to take the gun again.

great B movie...