So I figured it is something like 'Use Reindeer Itachi's skills three times in a row'. Possibly use 'Gift Whirlwind' three times in a row.
Showcase of custom-made characters
Leaf characters:
Katsuyu - Manda - Gamabunta - Tsunade (Invasion of Pain) - Tonton (Support Character) - Shizune (Support Character)
Rain characters:
Konan (Invasion of Pain) - Konan (Paper Butterfly)
Mist Characters:
Mei Terumi (Intro) - Mei Terumi (Angry) - Alliance Mizukage Mei Terumi Kid Haku - Edo Tensei Gengetsu Hozuki - Edo Tensei Utakata
Waterfall characters:
Chomei - Fuu - Edo Tensei Fuu
Akatsuki characters
Uzumaki Karin (Akatsuki) - Guren
Leaf characters:
Katsuyu - Manda - Gamabunta - Tsunade (Invasion of Pain) - Tonton (Support Character) - Shizune (Support Character)
Rain characters:
Konan (Invasion of Pain) - Konan (Paper Butterfly)
Mist Characters:
Mei Terumi (Intro) - Mei Terumi (Angry) - Alliance Mizukage Mei Terumi Kid Haku - Edo Tensei Gengetsu Hozuki - Edo Tensei Utakata
Waterfall characters:
Chomei - Fuu - Edo Tensei Fuu
Akatsuki characters
Uzumaki Karin (Akatsuki) - Guren