Urza's Saga 7
Everything about this card entices and excites. As you read on it just carries on delivering. I love the name, I love the types, I love the effects. It is epic. The pricing structure on Modern Horizons rubbed me up the wrong way last time round and I assume it will be the same this year. Opening with a card of this design calibre is a great way to get me on side. So, is this card good? What does it do? It is a land, an enchantment, a saga, a tutor, a mana source, a threat. This card does a whole lot of stuff very cheaply but it does it slowly. As a land drop this sucks it multiple ways. It is vulnerable to removal due to the extra types and it puts itself in the bin after a few turns anyway so unless you are finding actual power from your deck it is a land with a very limited mana output. Broadly this is not the sort of thing you want to open with. I am sure it is sufficiently broken that it will be a great turn one play in plenty of combo decks but more fair play decks will aim to have this be a much later land drop or better still something they cheat into play. It is one of those cards that is just everything positive, it costs you no cards nor mana, only a land drop, yet generates you both in a selection of ways. Thanks to how saga triggers work this can be three mana over three turns or it can be a sink of four mana to generate a pair of construct beaters, or indeed a mix of the two before it cashes in for your trinket. While this card is all good value it is slow acting and thus remains quite fair. I am happy playing this in any deck with sufficient targets for it to find. The range of utility if offers across the board is just far too enticing to turn down. Part Horizon land and part planeswalker. This will have plenty of homes from the obvious generic artifact ones to some more exotic brews. It is likely a little on the narrow side for unpowered cube play on the whole in much the same way that Trinket Mage is. When your 3rd age trigger gets you nothing the card is rather underwhelming so you need multiple targets and that is not easy when there isn't the extra volume of them courtesy of the power.
Diamond Lion 3
LED on a 2/2 for 2, pretty simple stuff. It takes the danger somewhat out of the LED element by adding two to the cost, adding vulnerabilities, and giving it summoning sickness. They increased the scope of the card by giving it the creature type and stats in payment for making it safer. It is too low powered on the creature side and too narrow on the mana side to make it into many cubes outside of the very combo focused ones however I am sure this will work its way into combo decks all over the place from modern to EDH thanks to being a cheap burst mana source. Almost all of them do eventually!
A much better Conch Horn, or indeed a generally worse Brainstorm. Having this effect on a colourless 1CMC permanent is a pretty big deal and so this will see plenty of play. Being able to break up the costs into 1 and 2 mana takes some of the sting out of the cost, which is savagely high for card quality. It is a little power light and low tempo for most cubes. I might consider it if I had very strong artifact or miracle themes on the go. I might also look at this in slow white decks as they ache for cards like this. Worthy of testing as it is convenient with a known to be powerful effect that is hard to come across.
Yusri, Fortune's Flame 1
A fun card and a strong one for those who like to flip coins in commander. Yusri is surprisingly close to good for a coin toss card. It gives you options and it evens out RNG with a lot of potential flips all in all resulting in a cool little card.
Flametongue Yearling 8
This is clearly great. It is tempo and value all complete with scaling. There are really only two downsides to this card. It is useless when your opponent is dorkless and it is RR to play making it a little narrower and a little more awkward to blow people out with early. The best mode for efficiency with this is at two where you get a reasonable body and reasonable damage outlay for the cost. As you move up to four and six mana modes the mana efficiency dwindles but the card remains decent tempo and value none the less. There is certainly enough creatures and heavy red decks that this will see sufficient play. It will be a decent help to the budding midrange and control red decks too. The more I look at this the more I see a kind of creature slant on Searing Blaze.
Thrasta, Tempest's Roar 2
Huge green dork. Questing Beast's big bro. It is pretty hard to get the cost of this down effectively in an unpowered cube. You have some free artifacts, a handful of free viable free spells, and then some less suitable but acceptable cheap cantrip style things. Paying consistently less than six for this seems very hard in any sort of unpowered cube setting and that is probably that for the limited side of things. Obviously in powered cube the existence of things like Mox Emerald and Black Lotus make cheating this out almost trivial if things are going well. I am not sure how much you want a big dumb dork in such places or if the consistency will be high enough but the power certainly isn't lacking. You can also build around this in rotisserie style events but without more green storm style payoffs I am not biting. If you only have one payoff you want it to win, this is powerful for sure but it isn't a win, you need more on top and so we need to see more cards in this kind of range.
Unmarked Grave 3
Very bad Entomb this is. Likely still good enough for decks that want such things. Might well need to make build concessions based on the non-legendary clause but that just leads to variation which is cool. The only thing I wish is that this and Entomb were closer and had pros and cons rather than on being a Lightning Bolt and the other a Volcanic Hammer. Chain Lightning and Incinerate make for a much more interesting pair with near identical combined power.
Profane Tutor 6
While this isn't in the same league as Vamp and Demonic it seems like it is fairly comfortably in the next block down. It is cheap and clean with the delay not being too brutal. It is even abusable with the various cheat out free stuff cards. Almost certainly too slow and clunky for cubes without combo decks but as soon as you have them this is well worth it. It curves fairly nicely as a turn two play that lets you find something turn four and have all your mana up. A small delay is an advantage then as you invest up front freeing up more valuable mana later while gaining information in the interim.
Unmask but with a value mode. Being a bad lategame card is the only real downside of Unmask and so this is just all round great. If you are under pressure evoke it out, if not just roll it out as a two for one at four mana. This will perform better in more powerful cubes, the zero cost scales rather well with increasing speed of format. It will still perform great in normal cubes though. The four mana mode is good, the zero mana mode is often amazing. With cards like Recurring Nightmare and Ephemerate the name Grief is entirely appropriate. Same goes for the rarity... This is an effect black wanted more of for turn one which is great news. What scares me a little is that this is a modal card where both modes are really top notch. I have run Unmask in loads of decks and iterations of cube. I am pretty sure this exact card without the evoke would be decent in my cube. Not quite Gonti levels but not far behind. Certainly just Grief in 4 drop mode feels better than Chupacabra which itself is a solid and highly played card with a lot of parallels. Modal cards don't need to be powerful to be good, just suitable and Grief is very powerful and very suitable. Despite only giving this an 8.5/10 this is still a card I have put a little mental warning note on. This might be too good, but probably more for other formats than cube.
Rishadan Dockhand 6.5
This is pretty nuts. One of the few things that kept Port fair was that you were effectively paying two mana to deny one mana. It required that you use it skilfully. This bugger goes one for one on mana denial and feels like it could be really brutal in a list with powerful two drop lords, Aether Vials. low curve and the likes of Spreading Sea to back it up. Scary card. Will really hurt control. Or decks with billions of colours. Probably a useful tool to have in modern but I can't see it being too popular. I think this one card has a real chance of making fish top tier. As for cube it is a little more interesting. Blue doesn't really have many high tempo strategies that can exploit a card like this. Izzet tempo is presently the only one that springs to mind. Compared to Port this also has the downside of not being a land and not tapping for mana and generally being useful. If you are not tapping lands with this it is not worth it and so that commands a more well suited archetype than Rishadan Port does in order to perform. This is a little too focused and narrow while also not having quite enough in the way of homes for cube. It is absolutely the kind of card that gives a real push to archetypes and so perhaps this opens up some possibilities. To put that another way, this might be strong enough for it to be worth altering the build of my cube to provide sufficient support for decks that this will be good in. If it isn't and my cube remains as is then this little dude doesn't quite get there I think. A very similar storey to Clever Lumimancer I suspect.
Timeless Dragon 6
What is not to love? Utility, value, nostalgia. All good things. Have two big fliers. Or one flier and one land as you need. You can spend six on this or nine on this as required. It is not a bomb card by any means but it is very user friendly and convenient. You can play it most places happily too. The only downsides are low raw power and a bit bland. Convenience goes a long way but this is fairly high cost. All told I think white has better things to do these days which is kind of a shame. This is the kind of card I love and that makes the game better but power is such now that you can do some really broken stuff with this kind of mana and so you probably should aim to be doing that mostly. Obviously I want this to succeed and will give it every chance to do so but I would certainly bet against.
Dakkon, Shadow Slayer 6
This is impressively well balanced. Normally three mana walkers are dangerous as they can come out before there is much in play to threaten them. If Dakkon does this he has sufficiently low loyalty that he isn't very exciting. Likely he kills a dork and gets some scry done. Good but not game breaking. You are better off waiting till you can get at least 5 loyalty on him so that you can instantly kill something and do so again shortly after. Unless you are killing stuff there is no value to be had with Dakkon. The -6 is a bit of a non event in cubes without combo. Nothing is big enough to make it worth the opportunity cost of exiling two dorks. Nice art, flavour, and balance. Sadly I think a little too narrow and fair to really stand out in cube. The kind of card that fits in but probably not getting enough action. Esper is a lot less common these days now that black and white have a decent depth in mass removal options. I will certainly give this a test as it is cool. Games go a lot longer and so I am perhaps undervaluing the power of making this for 3 mana four open to do other stuff and seven loyalty to mess around with. That might be game-breakingly good which is nice for a card you can play on three and have it be fine at worst.