This comic would probably be from the 70s and belonged to my father, but unfortunately got lost when moving house. It was in Spanish, but I wouldn't be surprised if it was translated from a different language -or was inspired by some other original sources.
There were multiple stories. I remember 3, can't say if there were more:
- A colony spaceship that crash-lands on a sort of New Eden planet, with only a man and a woman surviving, leading to a sort of new Adam & Eve scenario.
- An abandoned space outpost in some planet (maybe Mars?) that seems fine except for the lack of its crew. The space travelers that arrive to investigate it shortly discover that when a given sun / planet alignment takes places, a portal opens and some sort of space barbarians cross it, killing everything they found (I think they might be riding some sort of horses, like the Knights of the Apocalypse?).
- An explorer in a submarine ship that goes underwater to find two humanoid figures fighting each other. The explorer manages to interrupt their fight but one of them is too badly injured and dies. The other recovers to explain they were the last survivors from two opposing factions in Atlantis. When the explorer attempts to go back to the surface to present his finding, they arrive to see everything destroyed by some sort of war (to which the survivor makes some remark about them sharing the same fate). The "Atlantean" goes back to the sea while the human falls to his knees in despair (either this was a homage to the Planet of the Apes, or I mixed two similar representations of the same idea)
The comic style was very clean and realistic.
- I couldn't find anything related to the first story in TV Tropes, but I'll use the new Eden / Adam & Eve keywords when searching more.
- In the second story, The travelers are killed, and the outpost is left abandoned, implying that the next visitors are likely to meet the same destiny.
- In the third story, the two Atlantean are naked, have some sort of fin attached to their ankles, so they swim better, and have long hair and beards. They might be of green colour, but I'm not entirely sure.
Although I don't remember any explicit sex, the realism of the picture made it adult-oriented rather than teenager / young adult. I'm pretty sure it was in colour.
I'm no longer sure it was in colour, and I can't say if the publisher / edition was Spanish or Latin American. However, I found Spanish comic book artist Esteban Maroto. His style is quite similar to what I think I remember, meaning this would probably have been written originally in Spanish.