New Planets travel to and from them

There should be several different planets that you can travel to, inside a capsule built to however big or small the player wants. On these planets there can be all different types of new and rare loot only found on these planets, and there should be different mobs ranging from hostile to peaceful. Planets: Some planets that come to mind is a planet that is a twin from the current earth, but its drifted away from the sun and is full of snow, another could be a planet full of an exotic type of spider with heavily guarded loot etc. Mobs: Mobs include, creatures that have a suit of armor to protect themselves from harsh weather conditions  and they're hostile, and spiders are a tad bit more venomous that cave spiders another could be red hostile creatures with suckers (like an octopus) again hostile, but they're shape shifters, one last could be a peaceful helper from another snowy planet (not drifted) and they can either help get resources or help you build