Some ideas for books for demon slayer. pacifically demon blood arts
1 war flower... What it does: It grows a bunch of flowers in a 1 mile radius then explodes.
Effects: It decreases stamina for host, like in a game with a bar for it. Let's say it was at 100 it would go down to 50 after the attack. The host would use it in mid battle or not use it at all. If used at let's say.. 70 stamina left the host would pass out leaving some bad effects.
2 Flame spike.
What it does: It make spikes grown on host preventing attacks to make it through.. Let's say a demon slayer tries to attack host with the spikes. The katana would fully melt. Host can make spikes up to 8inches long.
Effects: will decrees hosts warmth making hypothermia more easy to get.
3 Flame control
Any flame around will change to (color of choice) when touched with the flame the demon is emitting which would let the demon control the flame and what it does and doesn't burn. And how hot it is. Like a 90 degree burn.
Effects: Awareness the host would be to focused on the flames to see what's happening.
4 Water freeze
What it does: This is like the flames. Any water in a mile radius will turn into ice and make it so the host can control the ice. If the ice melts it will be 450 degrees exactly. So if it melts on someone it will BURN them. This is with the hosts will. There are millions of possibilities with the ice, like a ice wall
Effects: If host messes up the melting it will melt on them to and it will hurt them. They have to watch out for themselves to.
I hope you enjoy my ideas. If you use them please give me credit. :)
Have a good day.