Unless you know ahead of time where enemies with a fatman will spawn, theres almost nothing you can do about it.
I'm sure raiders/super mutants/everyone would say the same thing about the SS if they still had a head.
Did he get headshot ?
http://gfycat.com/GreenEnchantingComet
And I love the more dangerous enemies in FO4.
They have the same ridiculous accuracy they have with grenades too, as soon as you hear that noise its usually already too late.
Which... I'm not sure how to program it, but that whoosh should have meant that it passed by overhead. Disappointed me the first time a sharp whistle was followed by an explosive death. For a quarter second, I thought I was safe
Personally, I love that the enemy AI can use any of the weapons as the player can; Fatman, Minigun, etc. Makes for some interesting combat and definitely keeps me on my toes during gameplay.
I had that happen as well, I could see the mini nuke heading towards me and it went to my left, so it either just missed, went through the open area or passed through the vertibird itself without exploding.
I remember the first time I ran into a Fatman wielding Power Armored Raider, it was in the urban areas and I wasn't even the one being targeted but some nearby feral ghouls......I was very low level, with limited armour so I got killed a few times before I even worked out what the hell just happened, then who was shooting at me and then how to work my way around fighting feral ghouls all the way to take on a raider, a turret and a power armored guy with just a pipegun.
I know that spot... it got me too until I worked out what was going on. Once I sniped the fatman guy in the power armour, his buddy picked up the fatman. By the time I had worked out how to get up to them and waded through ferals, the power armour raider had despawned. I got the fatman though, so some consolation.
Look on the bright side - at least you're not playing Dead-is-Dead.
(...you aren't, right? )
From an Army tactics manual I remember reading years ago:
1. If it can be seen, it can be hit.
2. If it can be hit, it can be killed.
The whole uber accurate fatmen/grenade thing has taught me to love the quicksave,that's for sure.
I honestly can't think of a game in the last 15 years that i have saved more times in per hour played than this.
Where it does take things a bit too far is when the player character becomes the primary target, regardless of anyone or anything else. I just had an attack on the castle that I fast travelled to, and a wedge of supermutants ran through the courtyard full of other defenders while chasing me, while I legged it round and rounds jabbing stimpaks...I think I got three full circuits of the court yard done, in a keystone cops situation.