Time for the Gruul top ten list although Gruul cards are not the most exciting of gold offerings. Not only are the Gruul cards not all that interesting or diverse, they are not all that powerful when compared to the cream of the other guilds cards. Gruul has a reasonable depth of playable cube cards however they have one of the lower average power levels. Most tend to be ways of killing artifacts or tempo dorks which are both things red or green have without need of combining forces. It occurs to me also that I have included questionable cards like Tin Stree Hooligan and Kessig Wolf Run in this list but omitted Kird Ape, Flinthoof Boar and Orcish Lumberjacks mostly for not having both red and green costs. The Boar should certainly be in the list and should be above Ram-Gang, although not by a lot, that is jsut an oversight I cannot be bothered to fix now. It is a flexible solid tempo dork that fills a gap in the agro three drops and gets plenty of play at present. The other two are more questionable for inclusion in this particular list but would both be top four if permissable and would significantly increase the quality of Gruul card. I could happily have the Lumberjacks at the number one spot, I love things that produce stupid amounts of mana. Forests as Black Lotuses you say? Yes please! Anyway, moving on to the more clearly Gruul cards.
12. Burning-Tree Shaman
11. Vithian Renegades
10. Sarkhan Vol
9. Tattermunge Maniac
(8. Kessig Wolf Run)
(7. Tin-Street Hooligan)
6. Boggart Ram-Gang
4. Burning-Tree Emissary
3. Huntsmaster of the Fells
2. Ghor-Clan Rampager
1. Bloodbraid Elf
Starting at the top and no surprises that it is Bloodbraid Elf, a 4 drop that is apparently too good even for modern. I am not a huge fan of the Bloodbraid, in singleton formats it is really rather random and works very poorly with certain cards, let alone less efficiently in a lower average casting cost format. All said and done Bloodbraid is still a fairly decent agro dork that comes with a free card. It is hard not to play it in any agro deck that can support it even if it won't be optimal with your Rancor.
Ghor-Clan Rampager at number two is more of a surprise, while it is just the ticket, its high rating is more to do with the other cards competing with it in this list than its overall cube power level. Combat tricks are really good at providing huge tempo swings and are generally underrated however this doesn't tend to make them playable in most formats. It is not the power of pump that is lacking but the situational nature of it. With bloodrush we are onto a winner as it ensures your card is never dead.Rampager was far from the first bloodrush card I tried out as I didn't like the gold aspect of it however it is the only one that offers substantial value at either end of the card. Sluaghterhorn was just a fairly irrelevant lacklustre threat and a sub par Giant Growth. Rampager is a solid enough threat when you have little else going on yet for two mana will be four or more to the dome or allow almost any creature to stop over almost any other creature with ease. The perfect utility tempo card for any agro deck that can play it.
Huntsmaster of the Fells is a card jam packed full of power but it is rather phaffy and doesn't fit all that well into many decks. He lacks any real direction which is a big part of why many decks don't really want him however as he does a bit of almost everything and is such a high power card you do find yourself playing him more often than the meta might suggest. Burning Tree Emissary is another high new entry that has been highly impressive thus far in a wide array of archetypes. She has been helping to recur Vengevine super early, she has been helping fix mana bases more often than expected, she even made a turn five Thundermaw Hellkite with no other ramp but an Aether Vial. Although slightly less abusable in cube without multiple copies to chain off with she is remarkably convenient and useful with many more undiscovered uses to come I am sure.
Manamorphose is both a great filler card and a superb combo piece almost in the same league as Frantic Search. Sadly with combo on the down and red and green having relatively few appearances in combo decks as it is the Manamorphose spends more time in the B cube than the A cube these days. It is also rare you have sufficient chaff in your pool that you are greatful to have it as padding. Other than Gitxian Probe it is the only card in magic that replaces itself in cards and mana which has to be somewhat of a claim to fame.
Boggart-Ram Gang has become a bit of a liability with undying creatures all over the place really appreciating a wither dork to get into tussles with. It is not even that good of a hybrid card as it is so colour restrictive, typically you can play it in less decks than if it were 1RG to play. It has has a lot of play for occupying a slot that is woefully under subscribed in both red and green who have very few aggressive three drops. Ram Rang fills a hole and does it fairly well but I really want more from a card as colour restrictive as the Gang.
Tin-Street Hooligan is the cheapest of the sex monkies and is far easier to splash than Vithian Renegades, goblin is also probably the better creature type for a red dork. Having said that the Hooligan works very poorly with Goblin Warchief and more relevantly Bloodbraid Elf. Burning-Tree Emissary has made it more tempting to splash but then you don't have to take much of a downgrade on your sex monkey to stay in colour. Overall a somewhat lack lustre card that gets a job done cheap if not always as well as you might like. And why is every single Gruul card hyphenated? Really tedious.
Tattermunge Maniac has been rather overshadowed by Rakdos Cackler and Dryad Militant. It used to be the limp yet incredibly playable one drop filler card. Hybrid mana on a one drop is so refreshingly convenient it goes a long way to making up for a the card being a really bad Savannah Lion. I suspect the Munge will never return to A cube play however prior to his recent departure he had racked up easily enough play to make this list. Sarkhan Vol, the best incarnation of Vol, is a card I am very fond of and have had surprisingly good success when playing him. Four mana is not a cool amount to be spending on giving your guys haste and that is most of what he does. I have not used him in a while and with so many of the more costly red and green dorks that have recently been added to the cube already having haste I think his limited value has decreased. That all said he does fit fairly well into most Gruul archetypes and has a good chunk of loyalty complete with a cheap and to the point ultimate. Obviously he fails in the most important planeswalker test of being able to protect himself but he is still a planeswalker and still wins plenty of games. Vol is also unique in that he sometimes wins with pump and haste, sometimes by spawning a boat loads of dragons and sometimes just by threatening stuff. On the back foot Vol is one of the worst but otherwise he will find a way to win within his arsenal.
Vithian Renegades is a minor tempo upgrade on your basic sex monkey. He is typically better in the agro decks than Hooligan, more so than a single power upgrade might suggest as it transforms it into a vastly more relevant thing to have on the board. He is also more convenient to use with things like Aether Vial and Bloodbraid Elf than Hooligan but his advantages only really work for him in the few agro decks that might want him and so he really doesn't do enough over the mono coloured cards or the more versatile Hooligan to deserve a slot in the cube. Sure, he is better than Viridian Shaman but he needs to be waaay better to get get in as a gold card. Burning-Tree Shama saw about as much play as the Renegades but is the more limited card. It is exceptional against many combo decks stopping them going off outright and will tend to get in a few extra pings against most decks however it is ultimately just a 3/4 in most situations, particularly with the decline of combo. The combo directly hosed by Burning-Tree Shaman where you create an infinite loop by use of various permanents are those that have suffered the worst decline. An OK body for its cost but with insufficient added value to compete with other cube cards even in the somewhat limp three slot.
Finally, here is a list of all the other Gruul cards that have seen play at some point in the cube that now reside in the B and C cubes.
Fires of Yavimaya
Radha, Heir to Keld
Surge of Strength