A curse passed down in Scandinavia.
It causes a person’s health to crumble with a mere point of the index finger.
Because it is necessary to take careful aim at the target, it is also known as a Gandr Shot.”
The fact that pointing at people is considered rude has its origins in this curse. Or something like that.
A particularly powerful Gandr is called a “Finn Shot,” and is capable of dealing direct damage to the target.
The sheer brute force of Rin’s Gandr already puts it on the level of a Finn Shot. Or more like, a Finn Gatling Gun.

Fate/side material: Fate Encyclopedia