"One of the most ridiculously overrated cards I've ever seen. This card sees literally zero competitive play in constructed formats (except maybe in Block? I don't play Block), and isn't even that interesting in casual play."
- Henrietta
So you don't play block... do you actually believe that means the ratings of those who do are irrelevant?
Take a look, 3 of the 8 top decks here used Flame Slash:
http://www.wizards.com/Magic/Magazine/Article.aspx?x=mtg/daily/eventcoverage/ptsj10/t8blockdecklists
As for casual, your comment shows a decided lack of imagination. As of this writing, an advanced Gatherer search shows 64 different creatures with toughness 4 and a rating of 4.5 or above; to kill such a creature for 
is a bargain.
With the thousands of MtG cards that have been printed over the years, surely you can come up with an "interesting" deck concept that utilizes Flame Slash.
Posted By:
helluin
(9/19/2011 8:37:55 PM)
Useful card. Cool artwork. Raymond Swanland reminds me of Richard Kane-Ferguson. They both have a style that really stands out.
Posted By:
SirZapdos
(11/14/2011 11:03:04 AM)
Reasons to hold your Lightning Bolts until your turn anyway:
Wee Dragonauts
Charmbreaker Devils
Gelectrode
Kiln Fiend
All of these creatures will allow you to get extra (better) mileage out of your instants if you cast them on your turn. Might as well swap your Lightning Bolts for Flame Slash with these creatures and use it to clear your path.
Just depends on the other cards in your deck.
Posted By:
alphagprime
(4/30/2012 11:01:17 AM)
Stuffy doll, just in case?
Posted By:
Kataklyzmik
(4/16/2010 3:22:47 PM)
Obviously it would be better as an instant, but in the long run, who cares? This kills so much stuff.
Posted By:
Laguz
(6/28/2010 9:18:53 PM)
Great for Pauper players on MTGO
Posted By:
AngelxLegna
(4/16/2010 9:05:16 AM)
I see no reason to complain about a 1 drop that will kill off Serra Angel no problem. It doesn't need to be an instant. If it was, no duh it would be better than Lightning Bolt, but bolt is the epitome of red and is perfectly balanced, so why do we need a card that is clearly better than it in all aspects? People worry about Power Creep in this game, saying Wizards is making cards too powerful, but they do it to please the same fans that complain that Flame Slash should have been an instant. Making a card more powerful than \ Lightning Bolt is asking for power creep, not balance. Bolt is good enough; if you want another bolt, then hope for a reprint. But if you expect a card to come out that is better than it in every way, you're asking for power creep to dominate all new sets.
Posted By:
sarroth
(4/28/2010 8:23:05 AM)
Perfectly balanced against Lightning Bolt. Everyone saying this is better has never played a real red deck, where so many games are ended with "double bolt you, good game." I still prefer Bolt and even Searing Blaze, but this is a good addition.
Posted By:
achilleselbow
(7/12/2010 2:49:22 PM)
1) Instant-speed removal is *very convenient* because it can easily generate 2x1 in response to enchants, giant growth-style cards, or other pumpers. it also allows you to cast it in the other player's turn, when you have the most information of what he's going to do, so you can take better decisions.
2) Not being able to hit players is... well, lame. As creature removal it's ok, but it's not fantastic; imho, it's just a bad-quality Path to Exile/Swords to Plowshares/Doom Blade/Go for the throat. But it's in red so it's ok, it's still one of the best creature-removal spells in red.
3) The comparison to Lightning Bolt is, imho, completely dummy. Lightning wins hands down. Still, the bolt is a versatile and powerful card that sets the "gold standard" for direct damage. The only case in which this would be preferred to the bolt is in a meta crowded with 4-toughness... (see all)
Posted By:
ninjabear
(1/19/2012 5:07:27 AM)
I have been gawking at this card for the last three hours almost more than any other out of all the packs I got. I seriously didn't realize until literally right now when I read this, that it was an instant. I didn't even look I just assumed it was! I was thinking oh my god man this is toooo good. For real, like too good. Not in a good way. I'm glad it's not an instant. I think this is going to get more play than everyone thinks.
Posted By:
EvilCleavage
(4/23/2010 9:48:37 PM)