questins just 4 fun?

Question

1) Lived in reverse, who or what could I be?
The incarnation of wickedness and evil - yes that’s me!

2) The sound of humor, happiness, joy, thrilled
Now add an ‘s’ it’s carnage, massacred, killed.

3) I’m there in darkness, but not alight
Can be seen in daytime, but I’m missing by night
I’m there in the shadows, but not in sight.

4)I begin and end with the letter 'e'
Have eight letters, but just one letter within me.

5) I start going and end up doing
finish everything and conclude nothing.

Answer 1

1) Devil
2) laughter --> slaughter
3) 'd'
4)envelope
5) 'g'

Answer 2

1)devil
2)slaughter & laughter
3)d & the letter d & a d
4)envelope & an envelope & everyone.
5)

Answer 3

i don't really ghet it