alarm
alert
attention
background
black
block
blue
bones
carbon
caution
computer
cross
crossbones
danger
dangerous
dead
death
design
end
evil
fatal
forbid
hazard
information
interface
internet
lethal
message
mortal
option
panel
prohibit
risk
round
sign
skeleton
skull
stop
symbol
texture
threat
toxic
venom
virus
warn
warning
web
website