Ancients Awakened/Subzero Serpent Strategies

The Subzero Serpent is a Pre-Hardmode boss that is an alternate to the Desert Djiinn fought in progression. Compared to the Desert Djiinn, the Subzero Serpent is far more difficult due to various reasons.

Terrain Preparation
The Subzero Serpent can and should be fought in area where, when the Serpent erupts from the ground, it can be hit as much as possible in its head, as the head is the only area capable of being harmed. If the player is unable to find or create an arena with these features, a flat, open area is a good alternative.

Armor

 * / are great overall armor sets for any class, and considering how long Subzero Serpent fights may take, the defense and regeneration provided by the Crimson armor is a superior choice to the Shadow armor. Nonetheless, in this fight, defense is defense, and should be considered.
 * may be a more preferable choice for any class, due to its damage resistance and high defense, which will allow for the player to tank more hits from the Serpent.
 * If the player has defeated The Broodmother before fighting the Subzero Serpent, is a great choice for all classes, but an excellent choice for melee users, since it, in functionality, is a stronger version of the Viking armor.
 * is a very powerful choice for mages, and is best paired with either burst or high damage magic weapons instead of rapid firing ones.
 * is a good choice for summoners in every scenario but this one, due to the Subzero Serpent's speed, 'small' size, the AI of minions at this point in the game, and only being able to be hit in the head.

Accessories

 * are great for getting out of the way of the Serpent and its minions.
 * or any of its alternates are a significant help with jumping away from or around the Serpent's minions, but is not that useful in the fight otherwise.
 * can aid in damaging the Subzero Serpent and its minions by piercing their defense.
 * If The Broodmother has been defeated before fighting The Hydra, the may be a good option, but is severely overshadowed and outclassed by the almighty Worm Scarf. However, the two can be stacked to be able to tank even more hits.
 * is an all around great option for dodging out of the way of attacks, ramming into the Subzero Serpent to avoid taking damage from contact damage, and getting in extra damage.
 * is, like the Bulwark, an all around great option, due to the insane damage resistance it provides. And, considering how long and drawn out the fight can be, it may be necessary.

Melee

 * The, while weak, is helpful for hitting the Serpent when it's in the air.
 * The is great for piercing, and for igniting enemies on hit. It's use lies in killing the Serpent's minions.
 * If the player has killed the Desert Djiinn and Sagittarius before fighting the Subzero Serpent, the is an amazing source of damage to both the Serpent and its minions. It would be a good idea to pair this with the Depthwalker, or with the Incineration.
 * The, when paired with the Exile's Katana, can be a good duo for fighting the Serpent, as it can hit the Serpent from a distance; a great secondary to have when and if the player gets severely injured by the Serpent or when its airbourne. It would be a good idea to pair this with the Blazing Dawn.
 * The is a good alternative to the Depthwalker, with considerably more damage, but a slightly slower use time, as it can hit the Serpent from a distance; a great secondary to have when and if the player gets severely injured by the Serpent, or when its airbourne. It would be a good idea to pair this with the Blazing Dawn.

Ranged

 * The, with its high damage, can do considerably good damage to the Serpent.
 * , with its high firing speed and moderate damage to the Serpent, The Undertaker is a good alternative to the Musket
 * s are a good source of both Dot and contact damage against the Subzero Serpent.
 * If Sagittarius has been defeated before fighting the Subzero Serpent, s are an amazing alternative to Dragon's Spines, as it does everything that the Spines do, but with more damage, and a higher DoT.
 * The is a great weapon for dealing burst damage to the Serpent and tearing its minions apart. Though, it may not be advised to use.
 * The is a good source of burst damage, but isn't the most accurate. It is advised to only use it when the Serpent first launches out of the ground, and before it contacts the ground.
 * If Sagittarius has been defeated before fighting the Subzero Serpent, the is an amazing weapon to use in the fight, due to its high base damage, and its ability to shoot five bullets at once. Again, it is advised to use it only when the Serpent first launches out of the ground, and before it contacts the ground. Either way, with the spread of the gun, and the amount of bullets fired, it can be used somewhat reliably in the fight.
 * The, if the player can get Molten Bars before fighting the Serpent, is a good option for those who can aim it.

Mage

 * is a mediocre option for those who wish to primarily focus on dodging, as the homing projectiles of the Mana Blade can allow for a near entire lack of aim and focus, but lacks damage and piercing. It is recommended for a glass cannon loadout if the player is going to attempt to reliably use the Mana Blade.
 * is a good option, as the player can build up multiple scythes in a sort of "stack" while standing still. And, if the player is using the minimap correctly, can line up the scythes in the direction of the Serpent before having to move away. It is recommended that a Cloud in a Balloon is used for this strategy.
 * is an amazing source of both piercing and debuffs, as it, much like the Golden Shower, fires an infinitely piercing stream of poison, inflicting the Poisoned debuff upon hit. Amazing for dealing damage to the Serpent's minions, and for hitting the Serpent in the air, as well as when it returns to the ground. Firing the stream in a high arc is advised when used against the Serpent itself.
 * is a good source of burst damage, and explodes upon impact. Good for dealing damage to the Serpent's head.

Summoner

 * The /  are very powerful summons, even in this part of the game.
 * The is a good option if the player goes out of their way to get it.
 * The, if the player can obtain it, is a good source of damage, considering that it can inflict the On Fire! debuff.
 * The is an acceptable choice, as it can be placed anywhere. It may best be used to hit the Serpent when it's airbourne.
 * The is an acceptable choice, if the player is either unable to get the previously mentioned staffs, or prefers them over the previous staffs.

Throwing
s, no matter the class, are a good option, as the player is able to stack them up on top of each other in a single spot. It is heavily advised to use the same strategy as you would with the Demon Scythe for the Sticky Grenades.

The Fight
The Subzero Serpent, even if it is a small, fast, and tanky target, doesn't have a wide variety of moves whatsoever.

The three main attacks of the Serpent are ramming into the player, spraying frost fire breath at the player in a stream, and summoning Snow Serpents to fight for it.

Being able to tank attacks are advised, as standing still and attacking, with certain weapons, can prove to do more damage to the Serpent, and can be much easier than moving around.

General Tips

 * The Subzero Serpent is a very fast worm type opponent, so while it is not required that the player uses speed-boosting accessories or tools, it is still suggested.
 * It is best to use anything that increases defense, damage reduction, and anything with high contact damage.
 * It is recommended that you have at least a single row of platforms, as to be able to dodge out of the way of the Serpent better, and for possible strategies.
 * If the player does not have a Cloud in a Balloon, a is a good alternative, if the player knows how to use properly.
 * Subzero Serpent fights may take upwards of five minutes to beat, but it depends on how much damage the player is able to get in whenever it bursts from the ground.