Some advice from one new player to another.
Been playing Splinterlands for about 2-3 weeks now and would like to share some info that wouldv'e been helpful to me in the hopes that it could help new players.
My first piece of advice is to set up a Hive account, they send you free airdrops once you do and you also need to do it to access the many linked services to Splinterlands (Splintertalk, Peakmonters, Cardauctionz, etc).
Summoners are extremely important, you need a summoner that can summon the level of the monster card you bought/rented or else you will just get the level one version of the card you are playing. I made the mistake of buying some leveled cards that could not benefit me at the rank I was at because I still had a level 1 summoner. This happened a lot with cards a rented where I just happened to rent the top card on the list thinking it was the best option (max level Kron/Llama in Bronze thinking I was a boss). Trust me you will save a significant amount of your budget by grabbing monsters/summoners at the appropriate level you are playing at.
Sorry to tell you this but there isn't a single card that is going to carry you through this game. There isn't even a combination of a few,Llama/Kron took me out of Bronze within minutes but in Silver 3 got slapped right back down. My win rate was 50/50 maybe worse 40/60 until my rentals ran out and then I sank back down. There are far too many reasons for this as well: sometimes you can't play the splinter you rented, your oppenent has a collection of better cards, your oppenent has better versions of your cards, or the most common in my opinion is that you are matched with a more experienced opponent.
Rentals don't seem to be cost efficient on almost any level for new players. If you are trying to figure out if it is worth X to possibly get Y, in most cases it probably isn't worth using rentals to get to a higher threshold. Still rentals can be worth their weight, the knowledge you gain about the cards you rent and hopefully the newer cards you play against as you climb the ranks is just immeasurable. You may not be able to afford the best cards but you can find cards with similar stats/abilities and deploy the same strategies that you learned climbing the ranks.
Having a bunch of cheap cards leveled up is generally better than having one card that is more expensive. Some cards go out of rotation, not sure which or when, but we should probably figure that out.
Haven't seen any tier list or ranking of any sort that has been useful so I wanted to at least give a couple of better abilites and monsters that have those abilites(that are still affordable):
Self Heal - Sea Monster, Pelicor Mercenary (Unlocked in Gold League)
Tank Heal - Wood Nymph, Venari Crystalsmith
These two abilities are dominant all the way through silver league because their isn't much that can stop healing besides DPS (DPS seems to be the best option in general). Once in gold you get more access to the ability affliction, you have it beforehand but there isn't any monsters that really deploy it well.
Inspire - Demented Shark, Silvershield Knight
Life Leech - Vampire, Venari Bonesmith
Double Strike - Axemaster, Hobgoblin, Silvershield Assassin, Undead Minataur
Inspire seems busted when paired with double strike melee monsters, especially Silvershield assassin since it doesn't need to be in the first position. It can be devastating in blast matches and help take away divine shield armor quickly. It also allows a strong water team for new players, currently there are 4 or 5 water melee cards sitting under 3 dollars that would benefit from the buff.
Thorns - Djinn Chwala, Crystal Jaguar
Stun - Lava Launcher (Gold league), Pite Ogre, Spirit Shaman, Twilight Basilisk (Gold League)
Not going to explain thorns too much, if you played against it you know that it sucks if you have no ranged attacks. Stun has been the biggest x-factor ability in the game for me, it can literally win you games you don't have any business winning.
There are special cards that don't fall into any list that feel like must owns:
Chicken - 0 mana card that can be used to fill a spot, sponge a hit, or create certain spacing
Creeping Ooze - 1 mana slow that can be used similar to chicken but with the added slow
Gelatinous Cube Lvl 6 - Self heal with scavenger, wins most poison matches if set up correctly
Halfling Alchemist - Didn't buy into the hype and now its so expensive but worth it.
Now I leave you with my last trailing thoughts, I generally favor neutral cards becaise they can be used in all decks. I share a similar feeling for dragon justt to a lesser extent because it can't be used as often. It is probably best to build one team at a time after that so that at the very least you have a strong chance of winning with your favorite splinter class.
Yodin Zaku and Byzantine Kitty are broken, if you ever get to see Magnor take out 4 people in one turn please have as good as a laugh as I did (outrage, trample, blast).