Hazards (Doom Supplement)
From D&D Wiki
These dungeon hazards are intended for the Doom campaign setting but can be used in any 5e futuristic setting.
Busted Steam Pipe
Superheated water vapour blasts from a leak or break in a pressurised pipe. The steam fills a 15-foot cone. A creature entering the area for the first time on a turn or starting its turn there must succeed on a DC 12 Constitution saving throw or take 1d6 fire damage.
A high voltage component has gone haywire, sending intermittent arcs of electricity to random nearby points. A creature ending its turn within 20 feet of the faulty electrics must succeed on a DC 18 Dexterity saving throw or take 4d8 lightning damage.
An area of high, low or antigravity caused by experimental technology, filling a whole chamber; or anomalies in spacetime effecting a smaller area. Noticing anomalous gravity is difficult, requiring a DC 20 Wisdom (Perception) check.
- High gravity
In a zone of high gravity:
- All creature's movement speed is halved.
- Jumping distance is halved.
- Only hovering creatures can fly.
- Falling damage is doubled.
- Low gravity.
In a zone of low gravity:
- Jumping distance is doubled.
- Falling damage is halved.
Upon entering a zone of antigravity, a land creature simply falls to the ceiling, taking the appropriate falling damage. This may be combined with high or low gravity.
Biohazardous liquid spills out from busted pipes or tipped-over barrels. It can cover any size area, but different depths pose different challenges.
- A surface spill poses no harm to any creature with any sort of armor. Unarmored creatures take 1 poison damage if they start their turn in the spill or move into it.
- Where the liquid has pooled into wading depths (2 feet or deeper) a creature takes 1d6 poison damage unless they are wearing medium or heavy armor. Pooled liquid is also difficult terrain.
- A toxic spill of submerging depths (5 feet or deeper) deals 3d6 poison damage. Biohazard sludge is difficult to swim through, requiring a DC 15 Strength (Althletics) check
An irradiated zone can cover an entire facility but usually only covers an area of about 300-1,000 feet. Whenever a creature enters an irradiated zone, at the start of its next turn it must make a DC 12 Constitution saving throw or take 1d4 necrotic damage and have its hit point maximum decreased by the amount of damage taken. If it succeeds then it takes 1d6 poison damage and may develop warts, rashes or other physical marks. It continues to take this poison damage until it leaves the zone but if it failed the save it can repeat it. Some groups make radiation trackers that turn red or play an alarm when radiation reaches a dangerous level. There are also suits made that are given to most scientists to protect them from harmful radiation. A creature wearing one of these suits has advantage on the save against the radiation and resistance against the damage.