As my first commander, I love Marath. However, being new to magic made my original deck quite terrible. After making a Riku deck that was decent, but never quite competitive, I decided to try Marath again. I decided to try a passive control, making a strange "pillow fort" style.
Are the Urza's lands really all that helpful? They have a unique synergy with Tempt with Discovery but outside of that, I think lands like Krosan Verge are probably more consistant. Other lands to consider would be the three in color check lands (maybe as an eventual replacement to the guildgates), Gavony Township, and Kessig Wolf Run for added utility. Chromatic Lantern and more ramp spells in general could help with color fixing.
Yeva, Nature's Herald is a card that I don't know is the best choice for a three color deck, as she is restricted to three creatures. If you're looking for a similar effect, you could try Winding Cayons in a land slot, or even Veldalkin Orrery.
Basilisk Collar and Skullclamp are two cards that Synergize extremely well. Gorgon's Head is a budget alternative to Basilisk Collar, but Bow of Nylea only gives deathtouch to attacking creatures, so you may not have it when you need it. It's still a good card, but I would suggest lookin at other deathtouch enablers alongside it.
Lastly, I would look at running more spot removal. Marath is a great source of removal, however if he isn't in play, or can't activate his abilities or whatever reason, it's good to have other options.
3 Marath, Will of the Wild
Creatures
1 Soul Warden
2 Jötun Grunt
2 Spirit of the Labyrinth
2 Budoka Gardener
2 Voice of Resurgence
3 Mentor of the Meek
3 Kitchen Finks
3 Eidolon of Rhetoric
3 Knight of the Reliquary
4 Angel of Jubilation
4 Heliod, God of the Sun
4 Nylea, God of the Hunt
4 Academy Rector
4 Iroas, God of Victory
4 Anger
4 Yeva, Nature's Herald
4 Trostani, Selesnya's Voice
4 Purphoros, God of the Forge
4 Windborn Muse
5 Sigarda, Host of Herons
5 Gahiji, Honored One
5 Kalonian Hydra
5 Xenagos, God of Revels
5 Seedborn Muse
5 Karametra, God of Harvests
5 Invader Parasite
7 Gisela, Blade of Goldnight
7 Elesh Norn, Grand Cenobite
8 Avacyn, Angel of Hope
8 Vorinclex, Voice of Hunger
1 Sol Ring
2 Swiftfoot Boots
3 Bow of Nylea
3 Godsend
3 Hammer of Purphoros
5 Gilded Lotus
5 Coat of Arms
Enchantments
2 Prismatic Omen
3 Aura Shards
3 Repercussion
3 Prison Term
3 Druids Repository
4 Mana Echoes
4 Bear Umbra
5 Doubling Season
5 Dictate of the Twin Gods
5 Gratuitous Violence
5 Mirari's Wake
5 Privilaged Position
5 Cathars' Crusade
6 Collective Blessing
Planeswalkers
4 Garruk Wildspeaker
5 Ajani, Mentor of Heroes
Instants
3 Krosan Grip
3 Rootborn Defenses
5 Fracturing Gust
Sorceries
2 Restore
4 Ranger's Path
4 Tempt with Discovery
4 Wrath of God
5 Primal Command
6 Austere Command
0 Command Tower
0 Selesnya Guildgate
0 Boros Guildgate
0 Wooded Bastion
0 Fire-Lit Thicket
0 Rugged Prairie
0 Oran-Rief, the Vastwood
0 Temple of Abandon
0 Temple of Triumph
0 Temple of Plenty
0 Temple of the False God
0 Stomping Ground
0 Sacred Foundry
0 Temple Garden
0 Selesnya Sanctuary
0 Copperline Gorge
0 Urza's Mine
0 Urza's Power Plant
0 Urza's Tower
0 Thespian's Stage
0 Dark Depths
0 Rogue's Passage
0 Evolving Wilds
3 Mountain
6 Forest
6 Plains
I want to add Grafted Exoskeleton and Kamahl, Fist of Krosa at some point
Are the Urza's lands really all that helpful? They have a unique synergy with Tempt with Discovery but outside of that, I think lands like Krosan Verge are probably more consistant. Other lands to consider would be the three in color check lands (maybe as an eventual replacement to the guildgates), Gavony Township, and Kessig Wolf Run for added utility. Chromatic Lantern and more ramp spells in general could help with color fixing.
Yeva, Nature's Herald is a card that I don't know is the best choice for a three color deck, as she is restricted to three creatures. If you're looking for a similar effect, you could try Winding Cayons in a land slot, or even Veldalkin Orrery.
Basilisk Collar and Skullclamp are two cards that Synergize extremely well. Gorgon's Head is a budget alternative to Basilisk Collar, but Bow of Nylea only gives deathtouch to attacking creatures, so you may not have it when you need it. It's still a good card, but I would suggest lookin at other deathtouch enablers alongside it.
Lastly, I would look at running more spot removal. Marath is a great source of removal, however if he isn't in play, or can't activate his abilities or whatever reason, it's good to have other options.
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[Pr] Marath | [Pr] Lovisa | Jodah | Saskia | Najeela | Yisan | Lord Windgrace | Atraxa | Meren | Gisa and Geralf