You can unlock Bruno for 15000 Battle Points or 399 dias/diamonds. Bruno is an offensive hero with 3 skills and one passive. Mecha legs as his passive, Volley Shot, Flying Tackle and World Wave as his casters.
Bruno Build Guide
The following inventory item build guide will increase his physical attack, improve critical strike chance, attack speed, and HP. The guide consists of 5 attack items and one movement.
#1 Tooth of Greed
Adds +75 Physical attack, Unique: +25% Lifesteal, nd Unique Passive-Frenzy: when Hp drops below 20%, the hero will receive an extra 10% physical lifesteal.
#2 Warrior Boots
Adds +22 armor and +40 Movement speed
#3 Thor's Sting
Increases his attack speed by +30% and his chance for critical is increased by additional 20% and 8% movement speed.
#4 Blade of Destruction
Grants him +75 physical damage and +20% Critical strike chance.
#5 Scarlet Phantom
Adds +30 to his physical attack, 40% Attack speed and 10% Critical strike chance.
#6 Endless Battle
Adds +50 Physical Attack, +25 Magic Power, +350 Hit points, +5% Movement Speed, +15% Lifesteal and +400 mana.
If you complete all this item and the game is not yet ended you may replace warrior boots by Blade of Destruction to add additional physical damage and critical strike chance.
There are other good builds for Bruno, but you must give this one a try. You will be surprised at what you can do with him on your side.