Lion's eye diamond

[Richardalcala]

{lion's eye diamond} I know a lot of decks use it including my storm deck but I still can't figure out how it is good to discard your whole hand unless you can play in the graveyard. Maybe if I cast {past in flames} then activated the LED. Well please let me know what you guys think or have seen I just don't know if I should buy some if my deck would be that much better. Well thanks.

[Gorzo]

There's a couple ways to use it. If you have a reanimator or graveyard-using deck, obviously is one. And if you play a deck like affinity where you tend to dump your entire hand, so you have nothing to discard, then you can use the free mana on activated abilities.

I'm sure there are more ways, but those are the two I know.

[Richardalcala]

I see it in a lot of storm decks and I don't get that is why I ask.   

[Xaol]

In {Goblin Charbelcher} decks! It's the perfect amount to activate belcher.

[Dudecore]

Dredge decks  use it.

[adventus]

I've got one that I'm willing to trade.  PM me if interested.
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It's a situational {black lotus}.

Imagine a deck full of zero drops, {ad nausum}, {yogmouth's will} and {tendrils of agony}.

Use while using ad nausum, draw your entire deck, play all of your 0 drops, then hit them with tendrils.