I realised prior to my little break I had not finished this series of top 10 cards for the various gold guilds. As the top 10 lists are so popular I am going to work on finishing them off starting with Golgari, a colour combination chock full of powerful and interesting cards. A long standing solid colour pairing that offers great versatility and synergy, each colour perfectly offsetting the other colours weaknesses. Most GB decks are generically just called rock decks however there are vast numbers of ways to build the deck due to the fantastic depth and strength of the guild. You can go very agro, you can go near creatureless, you can have a self mill or discard theme, a reanimate theme, a mana denial theme or a hand attack theme. You can do a bit of everything or nothing at all just playing the best cards in the slot. You can ramp hard, have a low curve or go straight down the middle. Over the years I would say Golgari has had more gold cards in the cube than any other colour and has continued to get great cards to add to the ranks and keep it strong even while other Guilds catch up a little in quantity and quality. 
10. Worm Harvest
9. Golgari Charm
8. Putrid Leech
7. Dreg Mangler
6. Vraska, the Unseen
5. Lotleth Troll
4. Maelstrom Pulse
3. Abrupt Decay
2. Deathrite Shaman
1. Pernicious Deed
Pernicious Deed and Deathrite Shaman are both so very good and somewhat different that I find it hard to pick between the two. Overall I think the Shaman is slightly better but in the context of being a Golgari card I have chosen Deed as the number one name. A big part of why Deathrite is so good is that you can play it in mono black or mono green decks which is less relevant in this method of grouping cards. Pernicious Deed is one of the very best mass removal cards on offer dealing with most permanent types and doing so at instant speed. It also allows you control over the effect thus increasing your chances of being able to engineer a favourable outcome for yourself. Deed is so strong it is often played in fairly agro decks than normally wouldn't consider mass removal as an option. Deed goes an incredibly long way alone in keeping certain archetypes like affinity and artifact ramp strategies in check. Both Deed and the Shaman would both be in my top five gold cards of all time along with Vindicate and Fire / Ice, they really are that extra cut above the rest.We probably all know already how good Deathrite is, getting banned in modern after a very short innings and being generally obnoxious in a wide array of other magic formats. It is not that he does any one thing so brilliantly just that he does so so very much at the bargain basement price of one mana. In the cube he is at his very best with sac lands and the like filling up graveyards with lands to eat and his two other tap effects come in incredibly handy in a wide array of match ups. He even a relatively beefy 1/2 when compared to the like of Birds of Paradise. The best way to summarise the little Shaman is that he is all good.
Abrupt Decay is the newest Golgari card to have fully established its place in the cube. Versatile and reliable cheap removal is an amazing tool in Magic, the cube being no exception. Uncounterable is a nice perk although not that frequently relevant. A lot of the time being instant speed also means it is not going to get countered but Decay has them both to be sure. Maelstrom Pulse is the slow unwieldy version of Abrupt Decay getting far far less play since it arrived on the scene. Pulse is one of the ultimate safety cards but it is rarely exciting. Even when you are killing multiple permanents, within the cube environment this mostly just means you are killing tokens.Lotleth Troll is a lot of monster for the price and reminds me most of a mini Spirit Monger. In reality it is a sexed up River Boa come Wild Mongrel that needs to offer strong synergy or methods of abuse to really warrant a place in any given decklist. Black and green love a discard outlet and can put it to use in a wide range of decks all the way to zombie bidding! Regenerate is not the defence it used to be and with an action card investment required per pump you typically do not want to overly invest in making the Troll a large threat. Great value and utility that is held back a little by his slightly narrow applications when push comes to shove.
Vraska the Unseen is really pretty bad compared to the good planeswalkers but being a planeswalker she is still unreasonably playable. Her best role is in sniping out other planeswalkers but then she starts to look rather like an expensive Maelstrom Pulse. The two loyalty walker you are left with should you use her to kill something right away is very easy to kill, slow to regain loyalty and not that threatening as something to have in play. With the really good planeswalkers you always feel like you have lost if they get to keep one in play for several turns. This is far from the case with Vraska, her ultimate is terrible, the best use for it is in humiliating opponents. It is almost always better to just keep Pulsing things they make with spare loyalty rather than trying to make silly assassins. It is hard to get a good two for one with Vraska, even when you lay her and use the +1 to make her only killable with at least 2 or 3 dorks you pass to option to you opponent just to ignore her and go to the face. Fine to play as good all round utility filler come removal but not something you can overly consider as a threat which is a very rare thing to be able to say about a planeswalker.
Dreg Mangler is one of the more surprising cards on this list. It is not played loads but is always impressive when it is. A 3/3 haste for 3 mana is very solid tempo and is particularly scary off the back of a one drop mana critter. It is the size of monster than tangles well in combat and cannot be long overlooked as a threat. The scavenge is then a late game kick in the teeth that comes along and adds a whole extra bunch of value at a point when everyones solutions are near spent. Giving +3/+3 to any body will make it a decent threat, put it on a flier, lifelinker etc and you are getting even mroe value. Sure, it costs five mana to do which is not cost efficient, but this just means you are not doing it till it is really good to do so or you have little else. Every time you do scavenge it completely feels like it was free to do, you don't feel like you had to pay the cost earlier by having a weaker card in the first place. Early game tempo and late game value on a direct card that is never something you could call dead. Such attributes rarely add up to a card not cube worthy.
Putrid Leech is a dullard of a card, it does nothing other than be very fat for very little mana. It hurts you a little but then most of the best cards do, certainly the black ones, and when in the right deck this should almost always be irrelevant. Only ever really showing up in dark zoo decks and really agro rock decks the little Leech does tend to perform very well, consistently dealing more damage than Tarmogoyf would.Golgari Charm has become far more interesting lately with Theros block adding a bunch of random extra enchantments into the cube. It has always been rather a clumsy card whose abilities rather counter certain different things rather than offering any particular synergy with your own strategies. Having a way to save one or more dorks is handy and potentially blow out good. Much the same can be said about -1/-1 to all dorks, especially at instant speed. Both are quite situational and are likely to be useful against the opposite sort of decks. With the generic enchantment removal aspect suddenly becoming far more widely useful the card has shot up in value. It is a dangerous tool for the Golgari mage although is in danger of being a meta choice.
Worm Harvest is the final card to make the list over many other very powerful options. It is the unique way in which the card works that makes it so interesting for cube play. It can be your main win condition and you can have it do so without ever having to tutor it up or even draw it. You can have it countered and just play it again and again until you have resolved enough to overwhelm and kill with. Obviously things like Life from the Loam and other graveyard focused things are the reason the card has so much potential but there is nothing else quite so convenient that is like it. Most commonly found in Gifts Ungiven style control decks and Death Cloud based denial decks but not restricted to those archetypes.
Finally here is a list of the other interesting Golgari cards that have seen a lot of play in the past or still see some play now in more niche decks.Cadaverous Bloom
Squandered Resources
Glissa, the Traitor
Grisly Salvage
Reaper of the Wilds
Shambling Shell
Skullbriar, the Walking Grave
Spirit Monger
Varolz, the Scar-Striped
Vulturous Zombie
Putrefy
Cadaverous Bloom and Squandered Resources are both great combo enabler cards. They are the non blue versions of things like Dream Halls and Mind Over Matter. There are a wide variety you can use either or both of these cards to fire off some mana intensive way of killings someone. Glissa is a lot of monster and offers some powerful returns yet is very hard to find suitable homes for and so despite her high power has never seen much play. Grisly Salvage is a very nice little synergic filler card that will help setup and fuel your engine simultaneously. Not a powerful card but a perfect support card in the right deck and the kind of card that makes the more unusual archetypes viable.
Reaper of the Wilds is a highly powerful midrange card that needs no building around to tap into the power like Glissa requires of you. You can get fatter dorks for the cost such as Polukranos, you can get more resilient dorks such as Thrun the Last Troll. Reaper of the Wilds does a bit of everything, it can trade up well, it can be fat for cheap and dominate the midgame. It can be very hard to kill and it can offer you card quality all the while being a very good creature with no downside.Shambling Shell rather died when they stopped damage going on the stack. It is a fine way to fill up a graveyard and offered a nice little combat trick to make combat awkward all on a body that was acceptably agro for the cost. Skullbriar is mostly a gimmicky card, Slith Firewalker is not really good enough these days and Mr Walking Grave is only the slightest of bits better. Zombie themed decks sometimes call upon this rare legend as does the occasional super agro rock deck but there are many better GB two drops ahead of this in the que.
Spirit Monger is another that has gone rather the way of Shambling Shell, despite the power creep it still looks pretty powerful for the mana and would be fine in loads of decks. The thing with Monger is it is all a bit unnecessary, you can do a lot more than make a serious threat for five mana, even if the threat isn't quite as beastly you are also getting something else done. The ways in which Spriti Monger fails to impress when next to a Thragtusk are countless. Alternatively you can make a threat as likely to end the game as Monger for cheaper that also does nothing else such as Phyrexian Obliterator, Master of Feasts or even just classic old Tarmogoyf. So despite plausibly surviving the power creep there is still no place for cards like Spirit Monger in the cube. Flavour wise it is still a total winner, little in magic compares to the feeling of impending doom you have as you repeatedly chump block the ever growing Spirit Monger just waiting for the time it is big enough to one shot you and your blockers get removed.Vulturous Zombie is an overlooked card that is actually far more useful than Spirit Monger as a game ender. The speed at which it ends games if you fire off a Mind Twist, Pernicious Deed or Death Cloud before your first swing with it is unreasonable. Kalonian Hydra is now the more reliable five mana super clock card but this does fly offering better defensive options and it is a zombie should you be all about the tribal themes.
Varolz, the Scar-Striped is a great fun card that you can use as a straight up combo with cards like Phyrexian Dreadnaught and Death's Shadow or just in a graveyard themed creature deck. He is a bit too niche to merit a slot without the also niche support cards but he is unique, interesting, versatile and fun. Finally poor poor Putrefy, a card once so staple and powerful that has befallen many a tragedy so that it now sees almost no play. The printing of Maelstrom Pulse, then Beast Within, then Abrupt Decay and then Hero's Downfall each took their toll. The decline in the prominence of powerful artifacts in most decks further detracted from Putrefy's usefulness. Fine filler card, versatile removal that is instant but does cost a fair chunk for what will almost certainly be a one for one trade.