There are exceptions as you point out, where careful use can hurt the land heavy guy, but generally Wildfire is a big payoff for ramping. Good card though.
Regarding MLD as an answer to ramp decks.....be careful. If the ramp player has already dumped a huge amount of lands into play (e.g. Boundelss Realms), it can be great. But often, particularly if they know that Armageddon is a possibility (so they don't commit every ramp spell they have), people with a lot of ramp are actually better able to recover from losing all their lands. This goes doubly for decks that diversify their ramp package - if they're mainly about fetching up lands, but run a few mana dorks, leaving them with a Fyndhorn Elves means they're only one land away from a Rampant Growth to kickstart the rampsplosion all over again. Natural Balance has this problem - it doesn't actually stop their ability to ramp, it just negates the ramping they've been doing. Not saying that MLD shouldn't be part of the anti-ramp package, just that lines of thinking like "he's got 7 lands, we've got 4, so Ravages of War will hurt him more" are often wrong. A well timed MLD spell can really set back a ramp deck. A poorly timed one can give them the game.
As a more general attitude though, don't be afraid to interact with their ramp. Nature's Claiming a Sol Ring is not a bad play. Counterspelling a Harrow is a good play. Flashing in Aven Mindcensor in response to a Skyshroud Claim is well worth doing. Cracking a Strip Mine on a land that taps for more than 1 mana is generally a solid move. And note that all these cards are just generally good and should usually be run anyway if you're in the colour.
I'll also second the vote for Meltdown. Such an underplayed little card - if you're not reliant on artifacts for ramp (e.g. a GR deck), it can do so much damage to other players' acceleration when fired off at something like X=2 early in a game.
I feel that cheap draw is something many EDH players overlook - whether black cards like this and Night's Whisper or the good blue cantrips or even some of the newer green versions like Oath of Nissa. They're not big splashy plays, but they smooth out your decks' performance nicely, let you get away with otherwise dubious opening hands and are worth playing at any point in the game - early on, they give you something to do with your mana, late on, you can cast them alongside another spell.
As for this one in particular, the "shock" mode it very rarely more than a gimmick, so Night's Whisper is gonna be better, but it's still well worth running in most mono-black decks, and a good number two colour ones, particularly if you've the fixing to reliably cast it turn two.
I've seen this do some good work in a Baru, Fist of Krosa deck. Overall, it's not a particularly good card, but there are certainly some decent interactions around which will make some decks want it.
I don't really see any problem with having some combos in a non-competative deck. I generally wouldn't build such a deck to be dedicated to assembling said combos (unless it's a pretty convoluted combo), but ultimately, I don't see the difference in a game ending on turn 12 to someone swinging with some random fatties, and a game ending on turn 12 to someone swinging with infinite Zealous Conscripts. Especially as there are plenty of non-infinite ways to completely swing a game.
That said, I often won't run cards that do nothing but combo. But if there are cards that are at least decent in the deck on their own, but go infinite with 1 or 2 other cards that also meet that criteria, then I'll happily put them in, and if I'm in a position to go infinite, I'll do so.
I think this is actually quite an interesting card. The problem with most of the symmetrical draw-7s is that, thanks to them costing a fair bit of mana, you're often the last person to be able to take advantage of the seven cards. As such, the only ones I really consider playable are those that can avoid this, usually by being cheap - Timetwister and Wheel of Fortune are the obvious two, Time Spiral has a higher setup cost - you need six lands - but once you're there, it's the best and Reforge the Soul can be decent if you've some topdeck manipulation. Unfortunately, barring RtS, these are not cheap cards monetarily (and even RtS isn't a dollar rare). And unlike some types of cards, in this case, the budget alternatives are much worse - in addition to the maan cost, the blue ones typically exile thus preventing any looping - to the point of very rarely being worth playing outside of specific interactions (i.e Nekusar).
Game Plan offers you a potentially cheap draw seven. If you can find one player who's willing to invest 3 to refill their hand, you've almost got yourself a piece of Power. And while it might be the weakest of them, it's still pretty darn good. How likely this is will very much depend on your playgroup - both the people and the decks they're playing. But if you can't get your hands on the really good draw-7s, I think this could be worth giving a shot in blue decks that are good at deploying their hands and thus would want a refill.
It's also a kind of interesting one to play against. While the answer to group hug cards is normally a firm "no", there are going to be plenty of times when investing some mana into this is going to be the right choice. If the deck playing it is known for cheap combos and you have a full grip, it's not a good idea. But spending 3 to refill your hand when you're pretty confident the caster isn't going to go off this turn can be a very good deal.
Aggressive, competitive and no infinites? Seems that you want to be playing Edric, Spymaster of Trest. Evasive 1 drops, counterspells, a couple each of extra turns spells, overruns and recursion and you're set. It's also pretty cheap to put together - things like Force of Will and Mox Diamond are very nice to have, but not by any means necessary. You probably wont have that many tools for dealing with other people swinging at you, but you don't really need them, as there's very little that can outrace an Edric deck outside of combo, and you've got countermagic to deal with any overwhelming threats.
There's a good Primer over in the multiplayer decklist forum.
This is one of those cards that is very strong but doesn't have that many homes. You want to be in Jeskai and have a decent amount of both creatures and non-creature spells. And you want many of the latter to be cheap so you can get chaining them. Plus you probably want to add green so you can untap mana dorks.
Still, if you are playing a deck that wants this card, it's going to be an incredibly strong engine.
For Orzhov, the two that stand out are Ayli, Eternal Pilgrim and Teysa, Orzhov Scion - having repeatable removal on the board allows you to play plenty of political games.
Queen Marchesa (Long may she reign) doesn't really do anything political on her own, but having access to reliable card draw gives you a better chance of getting to whatever political cards you're playing.
Anyway, the on hit effect is actually pretty good. Even without the various ways you can enhance it, hitting most creatures for three repeatedly will do a lot of damage to many decks' gameplans. The problem, as with all these dragons, is that they're 6 drops that don't do anything without hitting a player. Which can be pretty awkward. And the best way to help doing that, haste, is less useful, as you have to pay for the ability, leaving you needing 9 mana.
As a Saffi player, I'd point you at this thread, where there's some good discussion - the last page of posts between me and alblaster are talking about the deck in it's most tuned combo-centric form, but there's still plenty of information in the rest of the thread even if you're not trying to push it quite that far.
And I'll add my vote for a deck that makes use of the opponents stuff as something fun to build.
Regarding Ophiomancer, I wouldn't run it specifically as a blocker, but if you've other good reason to run it - for example, wanting repeatable token generation for sac fodder - it does indeed do a good job of discouraging people swinging at you.
And in general, this is my attitude towards blockers. I wouldn't really look to run cards in my deck just to stand in the way of my opponents creatures. But if there's something I would be considering anyway, having some good defensive attributes is a nice extra. Baleful Strix is another good one for this reason. It helps smooth out your curve early game, and if you have some kind of way to reuse ETB effects it gets very good, plus it has the nice bonus of being a flying deathtoucher - by comparison, I wouldn't run Tidehollow Strix as it does nothing but defend in the vast majority of decks.
The only real exceptions to this for me are cards that completely change combat, like Silent Arbiter. In the right deck, I'm happy to run purely defensive cards like that.
While ritual effects are certainly not something you just throw into any deck, they do have a place in this format. And this is potentially one of the strongest ones out there in terms of the amount of mana produced. However, it's also somewhat unreliable. To make it work, you need both a good density of mid-high CMC creatures and consistent access to something you want to spend the mana on. So, if you've a deck with plenty of 4-6 cost creatures and a 8+ mana general, this could be pretty good. That's pretty niche though.
Also, in a mono blue or blue heavy 2 colour deck, High Tide is probably going to be better. But if you want one ritual, a second can often be good.
As a more general attitude though, don't be afraid to interact with their ramp. Nature's Claiming a Sol Ring is not a bad play. Counterspelling a Harrow is a good play. Flashing in Aven Mindcensor in response to a Skyshroud Claim is well worth doing. Cracking a Strip Mine on a land that taps for more than 1 mana is generally a solid move. And note that all these cards are just generally good and should usually be run anyway if you're in the colour.
I'll also second the vote for Meltdown. Such an underplayed little card - if you're not reliant on artifacts for ramp (e.g. a GR deck), it can do so much damage to other players' acceleration when fired off at something like X=2 early in a game.
As for this one in particular, the "shock" mode it very rarely more than a gimmick, so Night's Whisper is gonna be better, but it's still well worth running in most mono-black decks, and a good number two colour ones, particularly if you've the fixing to reliably cast it turn two.
That said, I often won't run cards that do nothing but combo. But if there are cards that are at least decent in the deck on their own, but go infinite with 1 or 2 other cards that also meet that criteria, then I'll happily put them in, and if I'm in a position to go infinite, I'll do so.
Game Plan offers you a potentially cheap draw seven. If you can find one player who's willing to invest 3 to refill their hand, you've almost got yourself a piece of Power. And while it might be the weakest of them, it's still pretty darn good. How likely this is will very much depend on your playgroup - both the people and the decks they're playing. But if you can't get your hands on the really good draw-7s, I think this could be worth giving a shot in blue decks that are good at deploying their hands and thus would want a refill.
It's also a kind of interesting one to play against. While the answer to group hug cards is normally a firm "no", there are going to be plenty of times when investing some mana into this is going to be the right choice. If the deck playing it is known for cheap combos and you have a full grip, it's not a good idea. But spending 3 to refill your hand when you're pretty confident the caster isn't going to go off this turn can be a very good deal.
There's a good Primer over in the multiplayer decklist forum.
Still, if you are playing a deck that wants this card, it's going to be an incredibly strong engine.
Queen Marchesa (Long may she reign) doesn't really do anything political on her own, but having access to reliable card draw gives you a better chance of getting to whatever political cards you're playing.
Undead Alchemist
Anyway, the on hit effect is actually pretty good. Even without the various ways you can enhance it, hitting most creatures for three repeatedly will do a lot of damage to many decks' gameplans. The problem, as with all these dragons, is that they're 6 drops that don't do anything without hitting a player. Which can be pretty awkward. And the best way to help doing that, haste, is less useful, as you have to pay for the ability, leaving you needing 9 mana.
And I'll add my vote for a deck that makes use of the opponents stuff as something fun to build.
And in general, this is my attitude towards blockers. I wouldn't really look to run cards in my deck just to stand in the way of my opponents creatures. But if there's something I would be considering anyway, having some good defensive attributes is a nice extra. Baleful Strix is another good one for this reason. It helps smooth out your curve early game, and if you have some kind of way to reuse ETB effects it gets very good, plus it has the nice bonus of being a flying deathtoucher - by comparison, I wouldn't run Tidehollow Strix as it does nothing but defend in the vast majority of decks.
The only real exceptions to this for me are cards that completely change combat, like Silent Arbiter. In the right deck, I'm happy to run purely defensive cards like that.
Also, in a mono blue or blue heavy 2 colour deck, High Tide is probably going to be better. But if you want one ritual, a second can often be good.