There is a black market item for just about everything you can think of, so there is no "best item", just whatever fits best with what you're trying to achieve at the time. Morpheus arms are invaluable, because you can age your horse and keep training, competing, blupping etc, without needing to wait for an update. Golden Apples are popular with the younger crowd as they mean you can choose a nice new coat for your horse whenever you feel like it. And the black market tack items help your horses do better in competitions. Read all the BM descriptions of the items and see what you fancy. If you can't decide then it's best to save your passes and spend them when you really, really need something. You'll know when that is.
You can find all of the black market items by hovering over the breeding tab > the black market > all of the items are listed there with descriptions.
it is a item you get at the black market
BM stand for black market item.
You can either get it from the Black Market or buying them in the exchanges. They are easy ways to get them.
A BMI is a Black Market Item. A BMI is a special item or bonus that can only be bought for passes.
Black Market > Item you want to use > Purchase from stock / with a pass > Choose the horse you want it on > Validate
It's a Black Orchid, a Black Market item that completely restores your horse's energy, health, and morale.
black market > click on item > choose "use one from my stock"
There are several different ways to getting black market items on howrse. The most common way is to buy the items with passes, which can be bought (with real money), earned (through different ways, for example: every 5 karma points), being given a pass/black market item from another player, and/or winning passes. You can also obtain black market items by trading one or two black market items from your inventory for another item with another player who accepts your offer. Sometimes, Howrse staff are kind enough to give away free black market items to players whom complete certain objectives. (Like the September Calender 2011) - Ecclipze on Howrse
no unless you buy pass/passes and get the black market item!
Medusa's Blood is a Black Market item that costs one pass, and it turns your horse into a pegasus.
It depends on the BM item, but it is normally at 3 years old
You cannot buy it with a pass from the Black Market, you buy cards and if your lucky you can get the Apollo's Lyre.