This set is sold by the following vendors for 9,900 Honor Points:
Neutral: Ecton Brasstumbler in Gadgetzan
Neutral: Zom Bocom in Dalaran
Horde: Blood Guard Zar'shi in Orgrimmar
Alliance: Knight-Lieutenant T'Maire Sydes in Stormwind City
The legs and hands armor also drops from Occu'thar in Baradin Hold.
Ruthless Gladiator's Vestments is the Arena Season 10 Rogue set. It contains 5 pieces. Has set bonuses at 2 and 4 pieces.
Ruthless Gladiator's Leather Gloves
Ruthless Gladiator's Leather Helm
Ruthless Gladiator's Leather Legguards
Ruthless Gladiator's Leather Spaulders
Ruthless Gladiator's Leather Tunic
Wearing more pieces of this set will convey bonuses to your character:
2 pieces: Increases Agility by 5.
4 pieces: Increases your maximum Energy by 30.
4 pieces: Increases Agility by 6.
Here you can buy Season 10 Rogue Ruthless Gladiator's Vestments for EU or US Servers.
You'll get guide for getting Season 10 Rogue Ruthless Gladiator's Vestments