IO
An ancient and mysterious being of pure light, IO travels between dimensions seeking purpose in the bonds it forms with mortal heroes.
At a Glance
Core Principles
“IO is not just a hero; it's a bond, a connection, a promise that no ally fights alone. Follow these laws, and victory becomes inevitable.”
Choose Your Partner Wisely
You are defined by your tethered ally. Choose well, communicate clearly, and become unstoppable together.
The Global Threat
Relocate makes the whole map your playground. Your presence should haunt the enemy's every move.
Position is Everything
Your life depends on perfect positioning. Close enough to help, far enough to survive. Master this balance.
Timing is Life
Every Relocate is a commitment. Every ability has perfect timing. Sense these moments and execute without hesitation.
Enable, Don't Kill
Your power flows through others. You are the amplifier, the enabler, the force that makes good players great.
The Bond is Unbreakable
When you tether to an ally, you become one unit. Share their triumphs, survive their mistakes, and emerge victorious together.
Hero Overview
IO is the quintessential support enabler, a being of pure light that forms symbiotic bonds with allies to turn them into devastating teamfight machines. Unlike traditional supports, IO's strength comes from amplifying a single core hero through Tether's regeneration, Overcharge's attack speed, and Relocate's global presence.
IO's gameplay revolves around choosing the right core partner and playing as their personal enhancement system. Tether provides sustain and overheal, Overcharge grants damage amplification, and Spirits offer both damage and vision. Relocate is your ultimate tool - a global mobility spell that can save allies, initiate ganks, or secure objectives across the map. Success requires perfect communication, positioning awareness, and understanding your carry's power spikes.
Pros
- Global presence with Relocate
- Excellent sustainability through Tether
- Strong damage amplification with Overcharge
- Visually unique and hard to target
- Can save allies from impossible situations
- Works great with one competent core partner
Cons
- Highly dependent on team coordination
- Extremely vulnerable when caught alone
- Requires excellent game sense and positioning
- Relatively weak without a good tether target
- Relocate requires perfect timing and communication
- Can be completely negated by proper counter-play
Ability Analysis
Tether
ToggleIO forms a tether to an allied unit, sharing any regenerative effects and providing bonus movement speed to both units.
Notes: Tether copies movement speed from allied target, so buffs should go on the tethered ally, not IO. The tether range is 900, and if over 700 units away, IO will move to 300 units. Tether DPS works on creeps, neutrals, and even Roshan. Can hit invisible heroes.
Spirits
ActiveIO summons five spirits that orbit around it, dealing damage to enemies that touch them and slowing them.
Notes: Cast Spirits ~15 seconds before Relocating so you can cast them again mid-gank. Activate Spirits in fountain for free cast before TPing. With Agh's Scepter, manually explode spirits for quick burst damage. Spirits don't provide vision as they circle, but do when they explode on heroes.
Overcharge
ToggleIO and any tethered ally gain bonus attack speed and damage output, at the cost of draining HP over time.
Notes: Overcharge can buff non-hero units like Lone Druid's Spirit Bear, Warlock's Golem, and siege creeps. Toggle carefully as the HP drain can be significant. Perfect for boosting your carry's damage during crucial moments.
Relocate
ActiveIO temporarily teleports itself and any tethered ally to any target location on the map, then returns after 12 seconds.
Notes: Double-tap to automatically target fountain. Provides flying vision at destination during delay. Can be interrupted by disables, banishes, and some spells. Io must wait 3 seconds before Relocating back. Use the flying vision to create openings or check Rosh pit.
Tether (Aghanim's Scepter)
ActiveTether can be cast on any allied unit, and can be maintained even when the target is out of range. Drains additional mana per second when out of range.
Notes: Aghanim's allows you to maintain tether at any range, making global ganking much more flexible. The mana drain is significant but worth it for maintaining the bond with your carry across the map.
Developer's Notes
Developer Insights
IO is the ultimate teamplay hero that revolves around one critical relationship with a core ally. Success depends entirely on coordination and understanding between you and your chosen partner.
Key Insights:
- You only need ONE competent teammate to be effective
- Timing Relocate requires perfect communication
- Spirits should be pre-cast before ganks
- Tether positioning is everything - close but not too close
IO rewards creative playmaking and game sense over mechanical skill. Your value comes from enabling your carry to becomeunstoppable through perfect positioning and strategic relocations!
Game Strategy
Early Game
Timeframe: 0-15 minutes Objective: Choose core partner and enable through tether Key: Identify your main carry and stay tethered; Use Spirits for harassment and farm assistance; Position safely but close enough for tether range; Look for Relocate opportunities when your carry gets advantage Items: Arcane Boots (Mana management); Magic Wand (Burst sustain); Tranquil Boots (Map mobility) Tips: Stay tethered to your carry during laning for free regen; Use Spirits to secure ranged creep kills; Keep track of gank timing for potential Relocate saves; Communicate your Relocate cooldown to team
Mid Game
Timeframe: 15-30 minutes Objective: Execute Relocate ganks and teamfight coordination Key: Set up Relocate ganks with your core partner; Use flying vision from Relocate for objectives; Maintain tether during teamfights for maximum sustain; Save Relocate for crucial moments - kills or saves Items: Force Staff (Positioning utility); Aghanim's Scepter (Global tether); Glimmer Cape (Enemy save potential) Tips: Spirits should be pre-cast before Relocate ganks; Always ask permission before Relocating allies; Use tether range to stay safe while supporting; Watch for enemy disables that can interrupt Relocate
Late Game
Timeframe: 30+ minutes Objective: Win fights through perfect positioning and timing Key: Win engagements through Relocate positioning; Keep your carry alive at all costs; Use vision from Relocate for Roshan control; Adapt positioning based on enemy disables Items: Boots of Travel (Global presence); Scythe of Vyse (Disable for saves); Shiva's Guard (Survivability) Tips: Late game Relocate positioning is game-winning; Coordinate with team for multi-hero Relocations; Be aware of enemy Black King Bars; Save Relocate for opposite key times of enemy cooldowns
Tips & Strategies
Tether Mastery
- When IO is over 700 units away, it moves to 300 units from target automatically.
- Tether DPS works on creeps, neutrals, and even Roshan for extra damage and attack speed slow.
- IO copies movement speed from tethered target - so buffs go on the ally, not IO.
- Can hit invisible heroes, useful for detecting position.
Relocate Timing
- Cast Spirits ~15 seconds before Relocating so you can cast them again mid-gank.
- Double-tap Relocate to automatically target fountain.
- Provides flying vision around destination during delay.
- Can be interrupted by disables - save tether for last second when escaping.
Advanced Tactics
- Activate Spirits in fountain before TPing for free cast duration.
- With Agh's Scepter, manually explode Spirits for quick burst damage.
- Tether+Overcharge can buff non-hero units like Spirit Bear or siege creeps.
- Can start channeling TP while flying to Tether target for quick escapes.
Item Guide
Starting Items
Maximize sustain and survivability in early laning. Faerie Fire provides emergency escape when caught out.
Tango, Clarity, Faerie Fire
Core Items
Arcane for mana sustain, Wand for burst charges, either Tranquil for map mobility or Arcane for team mana. Boots choice depends on playstyle.
Arcane Boots, Magic Wand, Tranquil Boots
Situational Items
Agh's for global tether, Force for positioning, Glimmer for invisibility saves, Aether for spell range. Adapt based on enemy composition.
Aghanim's Scepter, Force Staff, Glimmer Cape, Aether Lens
Counter Guide
Good With
IO excels with heroes who can maximize Relocate ganks and benefit from Tether's sustain. Phantom Assassin becomes a nightmare with Relocate positioning and Overcharge damage amplification. Ursa and Ember Spirit can delete targets when delivered by Relocate. Lone Druid benefits from both Tethered sustain on the Druid and Overcharge on the Spirit Bear. Huskar and Sven gain immense power from attack speed bonuses. The ideal partners are heroes who need positioning help, have high damage output when properly positioned, or can snowball from early ganks. IO's value comes from enabling one core to become unstoppable through perfect support coordination.
Bad Against
IO struggles against heroes who can disrupt the core gameplay or punish positioning mistakes. Antimage burns IO's limited mana pool, preventing crucial spellcasting. Nyx Assasin can burst IO down before Relocate triggers and Carapace prevents damage. Slardar and Bloodseeker reveal IO's position and prevent escapes. Spirit Breaker charges across the map to find isolated IO. Silences like Skywrath and Death Prophet prevent Relocate casts. Stun locks from heroes like Lion and Shadow Shaman can interrupt Relocate at critical moments. High burst damage heroes like Lina and Tiny can kill IO before any reaction. The counters focus on preventing IO's core functions - mana management, positioning, and Relocate execution.
Good Against
IO dominates heroes who rely on positioning, have poor mobility, or are vulnerable to ganks. Sniper, Drow Ranger, and Crystal Maiden are easy targets for Relocate ganks with their low mobility. Channeling heroes like Witch Doctor, Enigma, and Shadow Fiend become helpless when Relocated onto. Position-dependent heroes like Tinker and Invoker lose effectiveness when suddenly forced to fight. Split pushers like Nature's Prophet and Terrorblade can be caught off guard. Squishy supports without escape mechanisms are prime targets. IO's ability to deliver a core hero anywhere on the map makes him a nightmare for heroes who rely on being at the right place at the right time. The global presence and unexpected ganks can completely disrupt enemy strategies and create insurmountable pressure through constant threat of Relocate.