Free Agent - NA
Over 4k HP, strong sustainable damage, good team fight presence build. Focusses on providing a large amount of HP items to gain insane amounts of tankiness without sacrificing the damage and protections necessary to play aggressive.
Flexible build with a pretty even split into physical and magical protections and works well as a slightly more aggressive version of more popular builds that include items like Sovereignty and other Aura items. From experience works well in Joust, Conquest and Arena although alterations are recommended based on team comp.
Benevolence
PASSIVE - While not near an ally god you gain 1 stack of Benevolence every second, up to a maximum of 50. Assists provide 4 stacks. While within 70 units of a hurt ally god you use up to 5 stacks a second to heal them and yourself for 1% of your Maximum Health. Each stack consumed provides you with 1 gold. If you overcap stacks they will still provide gold as long as you are near an ally god. Can be upgraded at level 15.
Glowing Emerald
Chalice of Healing
This consumable heals 250 Health over 25 seconds per use. Comes with 3 uses that are refilled if you enter the Fountain, sells for 0 gold.
Benevolence functions as an easy way to gain a bit of healing for teammates in lane but more importantly with be upgraded to Animosity for a further emphasis on basic attack damage alongside another spike in HP.
Gauntlet of Thebes
PASSIVE - Assists on a minion give 1 Stack and God kills and assists give 5 Stacks. Stacks provide 1 Physical and Magical Protection. At 45 Stacks this item evolves, providing an Aura of 10 Physical Protection and 10 Magical Protection.
Hide of the Urchin
PASSIVE - You gain +3 Magical Protection and +3 Physical Protection for each god kill or assist. At 7 stacks this item Evolves, providing a Health Shield that gains stacks every 2s. Shield only stacks if you have not taken or dealt damage in the last 5s. Each stack provides 10% of 100 Health +5 Per Level.
Manticore's Spikes
PASSIVE - When you hit an enemy god with Hard Crowd Control, they drop Spikes on the ground that lasts for 7s. When you or an allied god pick up a Spike, they gain a buff that causes their next ability to deal bonus Magic damage equal to 3% of their own Max HP. This effect lasts 15s and is doubled if you are the one who picks up the Spike.
Mail of Renewal (old)
PASSIVE - You gain 15% of your maximum Health and Mana over the next 3 seconds when you get a kill or assist against an enemy god or Objective.
Ethereal Staff
PASSIVE - Whenever you damage an enemy god with an ability you steal 8% maximum mana as well as 6% maximum health from the target. The Stats remain stolen for 60s and targets affected can have up to 4 Buffs and Debuffs at once. This can only occur once every 15 seconds.
Build starts of with Animosity, into Gauntlet to get going on the stacks necessary for good early game defence. Next is the Hide mostly due to the need for kills and assists in order to stack it which I find is better to get going earlier than later. Next is Manticores for another burst in HP, as well as the increase in ability damage that comes with its passive. Mail of Renewal is made second last as I find its the least critical defence item as it is mainly there to provide HP and an even split of protections. Lastly is Ethereal Staff which is an amazing damage item for Ymir as it grants him the ability to gain HP off his attacks and further wear down higher HP opponents. Overall this build aims to give as much health as possible without sacrificing the protections needed to avoid being quickly killed and also providing enough damage to support Ymirs aggressive nature.
Sovereignty
AURA - Allied gods within 70 units have their Physical Protections increased by 15 and their HP5 increased by 25.
Mantle of Discord
PASSIVE - If you take damage below 40% health you unleash a shockwave that stuns all enemies within a range of 20 units for 1s and become immune to Crowd Control for 1s. This effect cannot trigger more than once every 110s.
Emperor's Armor
AURA - Damageable enemy structures within 55 units have their Attack Speed reduced by 30%. Damageable allied structures within 55 units have their Attack Speed increased by 30%.
Four items that can be swapped in to further increase effectiveness against physical opponents.
Heartward Amulet
AURA - Allied gods within 70 units have their Magical Protections increased by 15 and their MP5 increased by 30.
Traveler's Cloak
Pestilence (old)
AURA - Enemy gods within 55 units have their healing reduced by 25%. This does not stack with similar Auras.
Four items that can be swapped in to further increase effectiveness against magical opponents.
Levelling order I find is more a preference with Ymir as long as you put consistent points into his Glacial Strike to maintain his damage. If you prefer setup level his wall or freeze and personally I choose to level his Ult whenever possible. More priority order goes as such 1) Freeze 2) Ult 3) Glacial Strike 4) Wall (Although I will prioritise wall more if the ADC or DPS characters I am working with are finding more value from it)
Opponents with limited leaps and dashes that can go through walls as well as gods with weaker poke damage as it provides greater opportunity for Ymir to cover distance without facing high amounts of damage.
Gods with easy access to slows and displacement based CC like Atlas, Bastet, etc who can move him into bad positioning and exploit his lack of escapes. Thus either making him require beads to provide a free escape or require items that can provide some degree of protection like Mantle of Discord to protect him in such circumstances.