NameTaken
Skeletron
well um, i sort of cheated by using google lol, but i couldn't come up with it without google, so yea
now try guess my second favorite (it's easy see hint above)
im probably right (i used google) but still could be wrong (very unlikely)
spoiler for those who still want to get it without cheating lol
i think its The Ragnarök from thorium mod
maybe specifically Dying Reality, the Ragnarök