If you describe a physical attack, accident, or injury as horrific, you mean that it is very bad, so that people are shocked when they see it or think about it.
horrendous
I have never seen such horrific injuries.
我从没见过这么严重的伤。
If you describe something as horrific, you mean that it is so big that it is extremely unpleasant.
horrendous
piling up horrific extra amounts of money on top of your original debt.
在你原有债务的基础上再加上数目骇人的几大笔钱。