Swamplands are very common, but rather small Biomes that can be found in any current Creativerse gameworld and are displayed in a pale emerald green color on the map.
The floor of Swamplands is usually made of common green Grass adorned with Tallgrass and Red Mushrooms, but more importantly, there are also at least small ponds up to large swamps made of green (non-poisonous) Bog Water with a bed of Mud with Reeds, Cattailss and Lily Pads inside. These plants can partly be used as Fuel in the Forge, otherwise they make nice decorations, for example in Flower Pots.
Weepwood trees with a lot of Moss on their trunks, Weepwood Leaves and rare Weepwood Flowers on top can only be found in Swamplands. On Weepwood trees common Beeswax or Queen Bees can be found and will additionally spawn over time.
Weepwood Flowers are a necessary ingredient for crafting Poison Bombs in your Crafting Menu, but can also be used as an ingredient in Basic Health Potions, Stone Mining Cells, Taming Collars, Golden Potions and Stamina Regeneration Potions - in crafting-recipes that will accept any kind of Flowers. These Flowers glow only very faintly, so they are not really useful as light-sources.
Weepwood Flowers do not regrow on Weepwood Leaves. An easy method to multiply Weepwood Flowers "infinitely" is to simply place blocks of Weepwood Flowers on the ground and pick them up again - once in a while you will obtain 2 flowers at once when doing that.
On the ground and even in the Bog Water of Swamplands, Weepwood Logs and Mossy Weepwood Logs might lie around. When Mossy Weepwood Logs are harvested, they will turn into blocks of common Weepwood Logs and (not always) separate pieces of Moss in the inventory of your player character.
These Crops can be harvested without any Power Cells and can be put in a Processor to gain 2 Seeds from them each, which can then be planted onto tilled soil next to Water to grow into Crops again. These Crops can be consumed directly or made into a large range of useful Food with different positive effects (Buffs) that can either be consumed by your player character or fed to Pets so that you can harvest from them.
In the night, Night Leafies and Night Pigsies usually populate Swamplands, but also Night Rocksters might be found, and Mirus next to entrances of Caves. From nearby Forests or Jungles other Creatures like Night Chizzards, Night Pigsies or Night Twiggies can traverse too.
Bog Water can only be scooped up with a Diamond Mining Cell equipped or better (Lumite Mining Cell), and can then be used in the Cooking Station to cook different kinds of Food, such as Bog Bread, Bog Sandwiches, or Bog Broth.
As is common for surface-biomes, Wood Treasure Chests can spawn on any solid block in unlit areas of Swamplands only during the (ingame-)night, from 10:34 PM to 5:12 AM (best at nightfall and only rarely in the morning).