So this is what just hit me. I started playing on this server: Non-pro, Easy, Mainly stock ZED, Address: 216.244.82.130 Port: 7727
And there was this guy named Kileddon(in the following uploaded image) who was using Portal Assassin teleporting me to the sky from my spawn and fall to death on map No_Mercy_Guards_fix. At first, I thought it was an accident, then, he did it again.
He abused his perk weapon and TKed me for no reason. I don't know what's wrong with him. And I just met him for the first time, or to say I actually noticed him for the first time for his purpose-unknown offense.