Koi are a carp and not poisonous.
Manta rays don't have stingers. They have tails.
Although they may not kill other fish it is not a good idea to put them in a tank with other fish with flowy tails such as guppys or sword tails. The take the tails as another male betta and will be very aggressive towards them causing stress and illness and possible death.
a jelly fish
Barbed stingers are stingers(bee stingers) that have those sharp points on the sides.You can find ''barbed'' on those cartoony lightning strikes.Instead of posting here,why not try searching yourself?
You can poison fish food. To get fish food and poison: get the Poison in the room next to the kitchen in Draynor Mansion. The fish food is also at draynor mansion floor 2.
The phrase 'ten tails' would be 十本のしっぽ (juppon no shippo) in Japanese. However, the word十尾 (juubi) has been used in the anime 'Naruto' to refer to a demon called 'Ten Tails'. I wouldn't recommend using this word, as it could also mean 'ten small fish'.
yes
They do
Mermaids have the upper bodies of women and fish tails.
yes you can just take out the posion sack and the stingers
no fish don't have legs they have tails and gills.
fish hit the ground with there tails