One of the issues is that you’re probably running a bad deck. Jax is fine I guess but there’s lots of better alternatives to Talon. Trying posting your decklist for starters.
Having trouble with Magmar
Raq has got a point, Lyonar’s matchup against Magmar is honestly fairly even, it really depends on your decklist, since if youre running Jax Truesight and War Talon, then youre deck might need a look.
Silverguard knights, Lysian Brawler, Beam Shock, Martyrdom, Tempest, War Surge, Divine Bond, Sunstone Bracers, Dragonlark, Piercing Mantis, Mirkblood Devourer, Skywing (Obviously Skywing is a bad choice), Dancing Blades (It also saved me from some trouble), Primus Shield Master, Fire Starter, Death Blighter, First Sword of Akrane, Jax True Sight and War Talon
I lack Lyonar Cards since most of my cards are err… Songhai though I have Archlyte Sentinel
yeah my deck is strangely done by me
http://duelystdb.com/squad/build
deck builder, once you finish, press landscape, copy and paste link here
EDIT : Added a direct link
i totally forgot about planar scout and Arrow Whistler anways

I take it you havent got too many of the higher grade Lyonar cards?
What division are you playing in?
Bronze 25 actually i used the starter deck first but when I got in trouble handling Abyssian and Magmar (including vanar though I only met them once) so I made a custom deck to satisfy my needs in handling growing and swarming enemies

I am no Lyonar expert, I don’t play the faction. There are definitely people more qualified on this forum to help you out with this. What I can do however, is provide a basic VERY cheap decklist that you should be able to put together.
Most of these cards you will have, and the few you don’t are all common except Ironcliffe Guardian, which are rare but are an autoinclude in all Lyonar decks anyway.
The Skorn should cover your need for AoE, while I tossed out a lot of the one-ofs you had in this deck to boost its consistency.
I would’ve dropped Sword, but the fact that it has a scary body is enough to include it as a lategame minion and will work for you until somewhere in gold.
Modify the deck as you feel fit. If another player gives you advice on the forums, take it over mine, theirs is most likely more reliable anyway.
In fact, you might even wanna toss the tempests and include something else of more use, like Bloodtear Alchemists or Primus Fists.
interesting build though I lack those Azurite Lion, Suntide Maiden, Sunbloom and Ironcliffe Guardian
Ill sacrifice some monster to build it Thanks
wait is Sunstone Templar and Arclyte Sentinel valuable Lyonar cards?
No, they don’t see play in any meta deck right now, Ironcliffes should be your top priority.
Arclyte is used in some of the cheaper budget decks cause its easy to use and can serve as semi removal, tlhough Primus Fist is better, and no Sunstone Templar is never used.
What do you think of the deck Cass? 
Yours? Looks pretty solid as far as i can judge, i’d just remove the tempests for primus fists

and the Maidens for Holy Immolations, but i guess thats way too expensive right now
Yeah, I mentioned the tempest removal at the bottom :3
I intentionally excluded Holy Immo because it was epic and too expensive yeah.
Oops, sry, didn’t read that too closely 
Oh yeah and btw @OP, the Lyonar - Magmar Matchup is kinda lopsided in favor of Magmar, try to bait the Egg Morphs out, buff your Ironcliffes above 3 attack with roar to avoid plasma storm, and bank on cards like Jax, and maybe decimate and aegis barrier. I know that these cards are pretty expensive, but they are the best i can think of to tech in vs Magmar (and you already have a jax).
ALSO AVOID MAKANTOR.
I just beat somebody today in DIamond who let me hit a total of 4 Minions + General with a Makantor. I dunno why.
So might as well sacrifice those 2 monster thanks
ohh umm… Can i still handle growing monsters using that? or dispels would cover it for me? Sorry I haven’t tried dispel before so I have no complete idea how dispel works.
Dispell would get rid of the buffs, keywords and effects on it, like Earth Walker would return to 3/3 and lose grow.
Sun Bloom is an AoE dispell (2x2) and has infinite range.
BEWARE! You CAN dispell your own stuff, so try to avoid it.
Oh man, I won a game with my SaboSajj deck when the guy wasnt playing around Makantor himself, so I cloned it with Mirage Master and cleared his board
FeelsGoodMan
This is what the board looked like when the game ended. Blindscorch + Zen’rui’d the Silithar Elder 
He ended up using 2 Earth Spheres, so the game dragged on a lot longer than I was expecting lol.
It is my honest opinion from now on that Mirage master is busted 
to be real tho, i think it belongs to the kind of card that can be pretty solid but nobody uses them, feelssajman
Dem I didn’t know that disenchanting some monster is this sad
I have disenchanted Eight Gates, Archlyte Sentinel, Artifact Hunter and Time Maelstorm (Draugar Lord would join their ranks but I felt like there is importance to this monster so I didn’t disenchant Draugar Lord)
So far its good though I felt Blistering Skorn is risky. My first opponent is Vanar so I didn’t have a chance to test it against Magmar
Oh yeah what is the difference between a Normal type card and Mystic Card? I have an Orb Weaver and The High Hand Mystic Card though i felt like its just the color that made the difference

