Ruric and Thar are the two heads of an ogre chieftain who's always prepared for a brutal battle. Known to the rest of Ravnica as Ruric Thar, they charge in at every opportunity, slaughtering whoever gets in their path. Get in the way of that bloodied axe and your opponents won't be in one piece for long.
Your plan is to attack at almost every opportunity, forcing your opponent to make tough choices. There's a good chance you'll be able to change the outcome of combat by discarding a bloodrush card from your hand to pump up your attacker. If your opponent doesn't block, though, just keep the bloodrush card in your hand, or else cast it to get another creature onto the battlefield. If the game doesn't end quickly, enormous creatures like Ruination Wurm and Ruric Thar can push your opponent to the brink.
This deck has plenty of cards that make your big creatures even better, including the "split card" Armed/Dangerous. The double strike ability granted by Armed can make one of your unblocked creatures deal a game-ending amount of damage. A spell like Dangerous is usually used to lure away all your opponent's blockers so that the rest of your attackers get through to your opponent. But to make things interesting, you could spend six mana, use fuse to cast both halves, and watch your opponent's creatures get smashed into oblivion.
If you're on the hunt for some more Gruul cards to add to your deck, take a look through the Gatecrash set. Rubblehulk gets larger the more lands you have on the battlefield, and that carries over to its bloodrush ability, too. The red-green planeswalker Domri Rade is a great match for any Gruul deck.