I’ll just go ahead and assume you mean the difference between the cast patterns and not the spells.

Although, you could kill someone fairly easily with Diffindo if you hit them hard enough or in a critical area. Either side of the neck or anywhere on the abdomen would be easiest to cause a fairly quick bleed out.

Anyway.

Diffindo on the left, Avada Kedavra on the right.

I tend to lengthen the exit on Diffindo a tiny bit as I find it cuts a bit sharper and a lot better that way but, technically the start and end should be roughly the same length in terms of movement.

DIFFINDO ─ stupidest thing you’ve done?

nooooo its fine hahahah sorry omg

hahahahaha no its fine it was just me being shitty

life's so hard