That tiny clip uploaded doesn't show the context behind that altercation. It all started by me calling out, rather playfully, that their car was inadequate and inferior to ours. They got seemingly agitated by the statement as they started following us around. We eventually ended up at the front of the PD, where the actual event takes place. We ran there to seek shelter from these possible agressors due to the way they were acting previously (ramming our car and tailing us). They ended up getting out of their car, and the uploader's partner started shoving my acquaintance. It was at this point that I decided to step in and warned him. He didn't stop so I started shoving him back, and he started focusing on me. The situation escalated as he punched me once. Surprised, I told him not to repeat his foul action. Sure enough, he proceeds to hit me again after some pushing. This is when I, half-accidentally, pulled out my machete that I had on my person before hiding it again. This should've been a severe warning against the aggressors actions, but he yet decided to keep going with the punches. It was at this point that I decided to pull out my machete and actually tried to hit the assaulter.
Up to that point, his partner (the demo uploader) was quite a passive observer. However, when he realized that his friend was fleeing, he decided to run up to his car and attempt to retrieve a firearm from the trunk in order to help his friend in distress. It was quite obvious what was going on, as the man I was giving chase after tried to run up to his friend as if to seek help. It wouldn't baffle me if this was actually a planned attack on their part, and they only tried to seek enough provocation to justify their usage of a weapon. Well, nevertheless, I saw what was happening, and decided to act in order to save my life. It was not awfully clear to me whether he was actually getting a melee weapon or an actual firearm, but it wasn't anything nice in any case. I end up killing him, and sure enough, he tried to retrieve an AK from the trunk of the car. Right after that I ended up killing his friend and then I made my swift escape.
My view of the situation is that had I not acted on the man going for his trunk, me and potentially my friend as well would've both ended up dead. Thus I see my actions as completely justified. Also, as a rather side note, I would've been able to see him go for the weapon, if we are talking realistically. Taking that into consideration or not, I DID manage to save my life through my calculated actions.