Deadlock Rat King Guide – Best Build and Abilities

Rat King emerged in Deadlock on October 2, 2026, quickly earning a reputation as the toughest hero to take down. His playstyle blends tankiness with crowd control, making him a linchpin during team battles. Understanding his abilities and how to build around them is crucial for any player wanting to dominate matches with this character.

Since his release, Rat King has proven to be the most durable hero I’ve encountered. Prioritize maxing Royal Pestments and Rule, Ratannia! before focusing on health and select gun items. His lane phase can be challenging due to his size and attack speed, but once his banner is active, he becomes a decisive force in team engagements.

Rat King Abilities

Rat King’s kit consists of four abilities, each with unique cooldowns and upgrade paths. Grasping the nuances of these skills can turn the tide of any fight.

Scrap Grenade

This grenade emits three detonations within an 8-meter radius. Each blast deals 65 bullet damage with 0.6 weapon scaling and slows targets by 20% for four seconds. At the highest level, the final explosion slows enemies by 40%. Notably, both players and enemies can melee the grenade to knock it away, which means positioning when using it is key.

Scrap Grenade often feels underwhelming in open lanes where it bounces too far from enemies. It shines best in cramped spaces where the explosions can land multiple hits consistently.

Rat Swarm

A pack of rats scurries forward, clinging onto foes to bite for 8 spirit damage while stripping 1% bullet resist over four seconds. Targets can hold up to five rats at once, accelerating damage as more latch on. Enemies can shake off this swarm with ground or air dashes.

This ability is foundational to Rat King’s damage output. Combined with Tier 3 upgrades, each bite strips 2% bullet resist. Deploying Rat Swarm before firing gives you a strong edge, especially when you aim at the ground to ensure the swarm reaches enemies immediately.

Royal Pestments

Activating this grants Rat King a barrier worth 15% of his max health for six seconds. While up, there’s a 15% chance bullets are reflected back at attackers, ignoring resistances. This scaling means stacking raw health dramatically increases the barrier’s potency.

Tier 3 transforms the ability, capping incoming damage per hit at 250 and boosting the barrier to 25% of max health. This upgrade is why Rat King can endure staggering amounts of punishment.

Rule, Ratannia!

Rat King charges forward carrying the banner of Ratannia for up to 12 seconds. Allies within 24 meters receive a 3 m/s movement speed boost and immunity to slows. Additionally, they take 20% less damage during this time.

You can recast the ability to slam the banner onto the ground, dealing 200 damage with 1.2 weapon scaling and launching enemies into the air. It also slows affected foes by 40% and summons rats from nearby sewers to apply Rat Swarm. The flag remains for 12 seconds, and Tier 3 upgrades boost damage reduction to 35%, making this ultimate essential for controlling fights.

Rat King also has a stealth element: crouching next to vents allows him to enter tunnels, granting quick repositioning so long as he isn’t engaged in combat.

Rat King Ability Upgrade Order

Players commonly agree on prioritizing max upgrades for Royal Pestments and Rule, Ratannia! first due to their impact in survivability and team fight presence.

1. Unlock Rat Swarm Tier 1 to add a second charge.
2. Upgrade Royal Pestments through Tier 1 and Tier 2.
3. Progress Rule, Ratannia! through Tier 1 and 2.
4. Finish Royal Pestments with Tier 3.
5. Upgrade Rule, Ratannia! to Tier 3.
6. Complete Rat Swarm upgrades, leaving Scrap Grenade last.

Best Rat King Build

This widely recommended build focuses heavily on Vitality items to boost health and barrier strength, while including key gun and cooldown reduction gear for offensive and defensive versatility. You can import this setup in-game using Build ID 846557.

Choose additional Vitality gear that counters your opponents’ strengths after this core setup. For extra offense, Weighted Shots adds useful damage.

How to Play Rat King

• Stay cautious in lane given Rat King’s large hitbox. Activate Royal Pestments before trades to soak damage.
• Hold onto Rule, Ratannia! to secure objectives like Rift or Mid-Boss, coordinating with your team before charging in.
• Lead fights by initiating and absorbing damage for high-tier damage dealers such as Seven or Wraith.
• Be aware the charge locks most abilities except Royal Pestments, so plan ability usage accordingly.

How to Counter Rat King

• Avoid prolonged exposure to his banner, which covers a 24-meter radius (increasing to 32 meters with Tier 2) and lasts 12–20 seconds. Engage once it expires.
• Utilize ground or air dashes to shake off Rat Swarm bites quickly.
• Exploit his early-game vulnerability in lane; ranged heroes like Bebop with hook abilities punish his slow movement and large profile.
• Apply damage-over-time effects like Infernus’s Afterburn or Toxic Bullets to bypass the damage cap from Royal Pestments.
• If available, Cursed Relic can interrupt his charge, effectively halting his ultimate.

Rat King Lore and Voice Lines

Introduced as the self-proclaimed sovereign of New York’s rat-infested warrens, Rat King’s ambition is to declare Long Island as the independent territory of Ratannia. Before joining the game officially, he was a fan favorite and meme for over a year. His voice lines reflect his quirky and sinister personality, with over 100 lines from his Rat Swarm alone, including uniquely named rats like “Rabies Ronnie.” Valve has not officially disclosed his voice actor as of now.

Rat Swarm alone has more than 100 voice lines, and many of them name individual rats. My favorite is “Rabies Ronnie has a gift for ya. Surprise, it’s rabies!” Valve hasn’t named his actor, as far as I’ve seen, so we looked at the strongest candidate in our Rat King voice actor article.

FAQ

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Deadlock

Developer(s)

Valve

Publisher(s)

Valve

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