There are a number of hazards that a player may encounter when playing Astroneer. This includes hazardous plants, falling, suffocation, and active geysers. These hazards can harm the player – and most are potentially fatal.
Many can be found across all the planets, while some are native to only one world. Some can be dealt with, while others must simply be avoided. Offensive flora will respond to the player on foot but not seated in a vehicle.
Defensive Flora are plants that will not harm the player directly, and will only harm the player when they step on the plant or disturb it with the Terrain Tool. Defensive flora has a chance to drop a seed when dug up, allowing it to be replanted to gain even more Seeds, Research Samples or Research Items at the roots.
Offensive Flora will harm players from a longer range than defensive flora will, and are often more deadly, spewing clouds of acid, shooting exploding projectiles, or exploding on their own when the player gets too close. Offensive flora has a chance to drop mutant Seeds, which allows for players to plant harmless versions of the flora, which have blue spots instead of red. Mutant versions of the plant will not drop samples or create research items, and will drop the same seed when dug back up.
Geysers are vents of hot steam that appear on the surfaces of Desolo, Vesania, Novus, and Glacio. When the player walks into them, they will be launched into the air. While the geyser itself only causes minor harm to the player, additional fall damage could end up being fatal if the player is not careful. Like flora, geysers can be destroyed by digging them up, though they drop nothing.
Fall Damage is a passive hazard that players must be careful of. If a player is not careful, they could fall off a cliff or down a hole, with some hazardous flora also causing fall damage from knocking the player into the air. Fall damage can be negated with the use of Solid-Fuel Jump Jet or Hydrazine Jet Pack. One of the best ways to avoid fall damage, is to slide along cliff or cavern walls, as the game only considers it fall damage if you land straight down without any angle
When the player runs out of Oxygen, they start to suffocate, which can result in death. Therefore, while exploring, the player must make sure they have ample supply or access to a source of oxygen, i.e., a vehicle or a shelter. To expand their reach, players can use the Oxygenator and a line of Tethers. Additional Oxygen Tanks or Oxygen Filters can allow the player to operate further away from their network of tethers for a limited time. A Portable Oxygenator with a suitable power generator, such as a Small Wind Turbine, can reduce the worry of suffocation.
Worm Pits were a hazard on the original Radiated planet. They sat on the surface, awaiting players to unknowingly fall in, leading to instant death. Hard, black terrain sat at the base of the pits, making digging around them difficult without a Drill. Removing the soil around the base would leave the pit hovering in the air, but allow the player to gather any items that may have fallen in.
Worm Pits were removed in Patch 1.0.
Storms were a major hazard in the game. They were a giant, roaming dust storm, that could be heard from far away. When reaching the player, storms would be deadly if shelter wasn't found, with cubes flinging at the player until one made contact. Items and vehicles could be blown away or moved due to the high winds.
Storms were removed in Patch 1.0.
Cavern Lures were carnivorous plants that hung from cave ceilings and would ensnare and kill an astroneer if they managed to catch one with their dangling lures. They could be dispatched by digging around their bulb with the Terrain Tool. This would cause them to drop to the floor and explode, sometimes leaving behind 1-3 Research Samples, they also were quite dangerous due to its ability to phase through ground and try to kill the player .
- During one of the streams, Cavern Lure was once referred to as a "Red Dangler".
Cavern Lures were removed in Patch 1.0.
Tumbleweed was a formation of a giant lethal ball of spikes could be found blowing around in the wind on Arid planets. Getting hit by a single one was not fatal, but getting caught in the middle of a stampede could easily inflict multiple hits. If you are quick, you could get them with the Terrain Tool, and sometimes they would drop Organic which conveys the fact that this object is indeed a flora. The inhibitor mod was a great way to get rid of them. They generally spawned far enough away that you could stay put to avoid them, however they would spawn in sight, which made it look like they were waiting for you.
Tumbleweed were removed in Patch 1.0.
Acid Pots were pumpkin-shaped flora that released green clouds of acidic gas if players moved too close. These clouds would follow the player a short distance before dissipating. When the gas made contact it damaged the player, and could quickly kill them. They typically spawned in groups of three and could be dug up to prevent them from producing gas. They commonly had an organic research item below them, and harvestable organic blobs surrounding them.
Acid Pots were removed in Patch 1.0, replaced by Hissbine.