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GrimTools: Mage Hunter, Level 100 (GD 1.2.1.2) - Grim Dawn Build Calculator
I wanted to make a Mage Build for my ‘Fantasy MMO Team’, something that could be comfortably played solo, but would also offer unique benefits when played in multiplayer. And so here it is! Artcis Magus!!
Edit: Grimtools link, video and parts of the post updated following some of the suggestions from the Mad Master @mad_lee
Arctis Magus is a Mage Hunter that brings incredible frosty crowd control to the battlefield. The Mageslayer set with max’d out Olexra’s Flash Freeze can bring an entire fight to a standstill. The spell can stop Fabius in his tracks for a moment, and can interrupt certain enemies (like Zantarin when he’s preparing to cast his big sundering shotgun attack). Once frozen, Arctis Magus uses a number of other frosty attacks to unleash frostburn and cold damage onto nearby foes.
Flames of Ignaffar is the primary weapon of choice, with 100% Fire and Lightning damage being converted to Cold damage. This is your bread and butter spell, it lowers enemy DA, it gives them 30% fumble, it crits for up to 180k damage per tick, and has lifesteal bonuses added to it, helping to keep Magus’ hp topped up.
Be Chill
The build obviously has a tonne of freezing attacks:
- Olexra’s Flash Freeze, lowering enemy resistance to freeze by 55%.
- Trozan’s Sky Shard which in this build is really just there to proc devotions and add some additional frostburn damage.
- Blizzard devotion proc
- Frostdread Presence gives you and all allies within a 15 meter radius a 20% chance of Freeze Retalation
- Outcasts’s Frostbite x2 and Winter’s Chill augments on the necklace and weapons each give a 3% chance to freeze enemies for 2 seconds, which applies to all skills that use weapon attack. In this case, that means that every Flames of Ignaffar tick has a 9% chance of freezing affected enemies for ~1.1 seconds.
Tankiness
Freezing enemies and interrupting attacks dramatically lowers incoming damage, helping to make this build quite tanky for a mage. On top of that, the build gets 24% damage absorption from Maiven’s Sphere of Protection, 17% Reduction to Enemy Damage from Aura of Censure, then 430 flat damage absorption from Inquisitor Seal. Adding 30% fumble to enemies also helps to reduce incoming damage. If you’re really in a bind, you’ve got Mirror of Ereoctes to pop, and Nullification helps to clear any pesky Sundered or DoT debuffs on you or your team.
Damage
This build is not a ‘massive damage’ build, but it’s not bad. It has good AOE, and good resistance reduction (about 141% cold RR). Flames of Ignaffar gets a total of 133% crit damage with all buffs up, and gets ~6 ticks per second in. The build gets up to about 200-300k frostburn damage. The OA of this build could also be higher to better support the use of its decent crit damage.
Team Benefits
First and foremost, the CC that this build provides is second to none. Freezing the battlefield and interrupting Nemesis attacks is hugely helpful for reducing the overall damage that your allies takes. Freezing enemies also prevents them from healing each other which is a nice added bonus. 
On top of that, having wide damage reduction to enemies, and bringing max’d out Inquisitor Seals is a great way to further reduce damage taken by allies, as does the 30% fumble debuff from Endless Flame. Word of Renewal and its modifiers are great for DA, HP, CC reduction boosting, plus a touch of damage. Arctis Magus buffs team crit damage by 34%.
Video: Crucible 140 - 150
Enjoy!