Enchantment - Aura
Enchanted creature gets +3/+3
When enchanted creature dies put a 3/3 green Elephant creature token onto the battlefield.
I'll explain the number one thing I hate about Enchantments: it is too easy to get 2-for-1'd. Now it depends on the Enchantment, too. For example, I would have no problem playing Guard Duty or Pacifism, or even Arrest because those go on your opponents creatures. I would have no problem playing Words of War or Seismic Assault because those are Enchantments--not Auras.
I would however have a problem with playing Trollhide or Bonds of Faith on my own creature, to buff them. This allows your opponent to play any removal spell instant or sorcery or otherwise, kill the enchantment and the creature with one card, setting down your hand-size by one. If you fall behind on hand-size too much will almost certainly lose the game. Sure you turned your 2/2 Human into a 4/4 but your opponent would just play Assassinate next turn and you lose two cards.
This card on the other hand, thwarts that counter-play, with the exception of it entering the battlefield--I'll explain that soon. It basically doesn't matter if that creature dies, you still get something out of it. This is exactly the kinds of Aura's that see play, or are rather considered exceptionally powerful, such as Genju of the Fens, Angelic Destiny, or Rancor. Rancor has single-handedly won me games.
If your opponent is playing this card, just Incinerate or Doom Blade the targeted creature before the spell resolves. Your spell will resolve first, killing the creature, then the Enchantment is countered due to lack of targets, it never entered the battlefield, the creature left the battlefield before it resolved, so they don't get the token. Voila! 2-for-1'd on instant speed. This basically applies to all Aura's with the exception of Genju of the Fens because it may prove to be difficult to destroy a land on instant speed. Only Lavaball Trap and Dwarven Blastminer come to mind, both of which are conditional. (Well, unless you hardcast Lavaball Trap.*)
Quite an amazing card really, I mean sure it can be outplayed, but really any card can be. Even Emrakul, the Aeons Torn. 3/5, it's almost necessary if you are playing something like Aura Gnarlid.
* - Hardcast is a term me and my friends had come up with that you pay the cost written on the card. It has come up several times (especially with trap cards) when you don't choose it's alternative cost because you didn't meet the requirements. Such as hardcasting Archive Trap end of turn because the opponent didn't search the library, hardcasting Sickening Shoal so you don't have to exile a black card from your hand, or hardcasting Hand of Emrakul to keep your spawns to block.