Thanatos - Aggressive Penta-Killer

Pros:

- Very high damage (I've seen up to 1600 crits on basic attacks when full build with buffs)
- High mobility ( Scent of Death gives him up to a 30% movement speed buff when fleeing, or up to 60% movement speed while chasing an enemy in execute range. Stacks with Hovering Death)
- High sustain (His passive gives him a 10-20% heal from kills, as well as 75% of damage dealt from Death Scythe, Asi is just the icing on the cake)
- Plenty of Mana ( Transcendence gives more than enough mana, and a good chunk of physical power)
- Good escapes (The mobility and immune to slows is enough to get away from most conflicts, and if need be, you can use Hovering Death to flee)

Cons:

- High cooldown (Since there is no built cooldown, excluding Jotunn's Wrath, you need to make every ability count, don't just use them randomly. His passive should be enough to keep you going in a larger fight)
- VERY little protection (You will have to rely on your damage, movement, and lifesteal in fights)
- Low health (You'll need to avoid prolonged conflicts, and I would stay away from any mage that's hitting in the thousands, such as He Bo)

Harvester of Souls (Passive): Enemies within execute range are revealed to Thanatos, although invisible enemies ( Loki, Serqet, Nu Wa, and Ao Kuang) are not. Killing an enemy god heals Thanatos for 20% of the target's maximum health and reduces his ability's cooldowns by 5 seconds, while killing a minion heals 10% of the target's maximum health.

Death Scythe (Projectile): Thanatos throws a scythe out in front of him dealing damage and an additional 10% of the target's maximum health, while healing Thanatos for 75% of the damage dealt. Enemies hit are slowed for 3 seconds. Consumes 5% of Thanatos' maximum health on use. Note that this doesn't penetrate, so minions will stop it.

Scent of Death (Buff): Thanatos gains an immunity to slows, additional movement speed, and physical penetration for 6 seconds. The movement speed buff is doubled when moving towards an enemy god in execute range. Consumes 5% of Thanatos' maximum health on use.

Soul Reap (Cone): Thanatos swings his scythe in a cone in front of him, dealing damage, and applying a short silence. He moves at a reduced rate while using. Consumes 5% of Thanatos' maximum health on use. Note this can be used to interrupt dashes, and attacks similar to Fenrir's Brutalize.

Hovering Death (Ultimate): Thanatos flies into the air for 5 seconds, while in the air, he is granted a 150% movement speed before diving on a targeted location. Enemies within the targeted location are stunned for 1 second, and if they're in execute range, they are executed (killed instantly). Consumes 10% of Thanatos' maximum health. Note that Scent of Death's movement speed buff stacks with his Hovering Death's movement speed buff.

Since the builds are very similar, just adding a starter item for Joust/Conquest, I'll only go over the important ones.

Ninja Tabi/ Warrior Tabi: While most people go with Warrior Tabi for the additional +20 physical power, I prefer the +15% attack speed from Ninja Tabi, but either one works for the movement speed and damage that you need early game.

Transcendence/ Jotunn's Wrath: Sometimes it's hard to build stacks with Transcendence by killing minions, but getting stacks from player kills is much more efficient with Thanatos, basically having a guaranteed kill with Hovering Death. The mana from Transcendence (1050 with full stacks) is much more than the mana gained from Jotunn's Wrath (150), as well as the MP5 from Transcendence. Transcendence also grants more physical power (65 minimum when at full stacks), whereas Jotunn's Wrath only grants 40 physical power. On the other hand, Jotunn's Wrath grants 20% cooldown reduction, which is great on Thanatos if you're not using his passive to its full potential. Jotunn's Wrath also grants 10% physical penetration, allowing for more damage output on enemies with physical protection. I prefer Transcendence over Jotunn's Wrath on Arena, but Jotunn's Wrath may be better for Joust/Conquest.

Asi/ Bloodforge: Both grant a flat +15% physical lifesteal, however the passive from Asi grants an additional 25% for 5 seconds (With a 15 second cooldown), whereas the passive from Bloodforge grants a shield on kills and +20% movement speed buff for 20 seconds. Bloodforge grants a flat +75 physical power, whereas Asi grants +20% attack speed and +15 physical penetration. In terms of lifesteal, Asi is the superior choice, however with the change to Bloodforge with patch 3.8, I prefer it over Asi now.

The Executioner/ Ichaival: The Executioner is an awesome item for any basic attack oriented build, granting a flat +30 physical power, and +25% attack speed. Its passive reduces the target's physical protection by 8% per stack (max of 32%) for 3s on basic attacks, making it good when facing relatively bulky opponents. Ichaival is another great item for basic attack builds, granting a flat +30% attack speed, and +10 physical penetration. Its passive increases your physical power by +10, and reduces the physical power of the target by -10 for 3 seconds on successful basic attacks, making it better when facing a team with assassins and hunters.

Deathbringer: This is a must have on most basic attack builds, granting +50 physical power, and +20% critical chance. Its passive increases critical strike damage by 40%. This paired with how his attacks work (1, 0.75, 1.5) will do an incredible amount of damage.

Rage/ Malice: Rage grants +30 physical power, and +20% critical chance. Its passive increases your critical chance by +10% per stack (+60% max) every time you basic attack without a critical, stacks reset on a successful critical. Malice grants +50 physical power, and +20% critical chance. Its passive inflicts 75% of your physical power to your target as DoT on a successful critical. I prefer to use Rage, so that my critical strikes are more common, but the DoT from Malice is nice as well.

Bellona: Since this is a basic attack build, you'll want to avoid Bellona, as her Scourge will disarm you for up to 2.2 seconds, leaving you pretty much defenseless. If you're going to ult her, I'd recommend keeping track of her ult cooldown so you know if she can leap away or not.

Loki: A good Loki build can one shot you with his ultimate, so you definitely want to avoid it at whatever cost. His Vanish will hide him from the view of your passive, so ulting him is pretty much useless unless he's under crowd control, or his ultimate and Vanish are down.

Ao Kuang: Similar to that of Loki, he can shred you, although he does that without the use of his ultimate. Water Illusion is far worse than Loki's Vanish, as it also teleports him forwards, if you're on the ground, try to Soul Reap him if he moves towards you with it, it will silence him, and break his stealth. This ability to teleport, and enter stealth makes it relatively hard to use Hovering Death on him.

Kali: You do not want to be near her when she uses Destruction, as it stops her from dying while in it, and it deals AoE damage, although be ready to use Scent of Death or Hovering Death once it has run out. Incense is an AoE stun that lasts 1 second, however it buffs Kali by up to 50 physical power, this gives her several free hits (Kali generally has high attack speed) with increased damage, which can be enough to kill you if you cannot lifesteal for enough once the stun wears off.

Kumbhakarna: This is another god you want to stay well away from. He has 3 crowd control abilities on fairly low cooldown, and a passive that is rather obnoxious to deal with. Groggy Strike is a 2 second root with a range of 40, and a mere 10 second cooldown, easily stopping you in place for his team to kill. Mighty Yawn is an AoE "stun", although it is considered a mesmerize, it's basically a stun that lasts up to 3 seconds, with a 15 second cooldown, and if broken early causes up to a 40% slow, and 50% attack speed slow. Epic Uppercut is a dash, that knocks the target up for 2.2 seconds, dealing a minimum of 825 damage at max level (Protections and Power not taken into consideration). Sleepy prevents Kumbhakarna from dying, requiring up to 10 basic attacks to kill him, if he is not hit enough in 8 seconds, he awakes with 25% health and mana, this passive has a 240 second cooldown. Note: Kumbhakarna appears to be in your execute range while using his passive, but landing on him will NOT execute him. If Kumbhakarna is in your execute range, and his passive is done cooling down, it will activate his passive instead of executing him when landing on him.

Anyone with a crowd control ability on a low cooldown IS a problem, if you get stunned, or rooted for too long, you'll die 70% of the time. With the nerf to S3 Purification, you need to play smart, as you'll only be able to break out of a crowd control effect every 160 seconds.