pigs i have a lot off respect for them, iv had a few have a go at me and cut up some of our dogs real bad, but always when wounded. i however do not consider them "Dangerous game"
i really can't point out exactly what the drive is, like the others on here when it comes to Dangerous game.
for me when it comes to plains game it is more of a challenge of wit's, but with Dangerous game its more a challenge of focus and guts. you have a different mindset, different emotions because death is now shadowing the equation
staring down the barrel of a backup rifle with a big ol Water buff meters away finger on the trigger ready to squeeze if it explodes at you, fear is not on your mind...for me, more like a deep focus of energy and anger as at that moment you and the bulls flaring eyes meet and an age old instinct of battle between man and beast is in full circulation between the two of you, both you and the bull know there are 2 outcomes, you can see it in their eyes either you both back down or one of you is going to Die.
even a African Lion will do the same, and in my experience most of the time will take the option of backing down if you present it by doing the same. Luckily i have never met an animal that that has made the decision to take option 2. thats not counting wounded game they are in a different mind set!