Killstreak Fighting | World Ender showcase 

phase 0: 0 kills (100 hp and 0.65 dmg)
phase 1: 5 kills (650 hp and 66 dmg)
phase 2: 60 kills (25k hp and 666 dmg)
phase 3: 250 kills (666k hp and 6.6k dmg)
phase 4: 600 kills (2m hp and 60k dmg)
phase 5: 1k kills (6 trillion hp and 2.5 billion dmg)
phase 6: 10k kills max (inf hp and inf dmg +black sky and 5 times bigger sword)