Indeed,it is a good jutsu,I'll put it to good use.I have no more questions.
Ok,then for the first one.This is the first custom I ever made btw,more than two years ago

I think it's usage is pretty understandable,in a fight if you intent to use it,make sure to utilize the terrain,they can't be seen if there is some grass covering them for example.Also try to conceal yourself while casting it,so the opponent doesn't even know that there is something on the ground.
(Katon:Hitoshirenu Hisaki):Fire release:Hidden Flames
Type:Supplementary
Rank:C
Range:Short
Chakra cost:20
Damage: (15 whenever it's steped on)
Description:The user spits out tiny bearly visible sparks to the ground. They will continue to burn as tiny flame sparks almost invisible. If anybody steps on a spark it would engulf the persons feet/legs/lower body in a sudden burst of flames.