Io
Historical Balance Tracker & Intelligence
Balance History
6/22/2026
No hero-specific updates in this patch.
5/6/2026
Tether: HP/Mana Transfer decreased from 60/80/100/120% to 55/75/95/115%
Spirits: Now remembers the radius of the spirits between casts
4/7/2026
No hero-specific updates in this patch.
3/27/2026
Equilibrium: Max Damage Amp and Max Heal Amplification decreased from 5 + 0.5% per level to 4 + 0.4% per level
Talents: Level 25 Talent Attack Tethered Ally's Target Damage decreased from 75% to 50%
Patch 7.41Net Gain
3/24/2026Removed Wellspring innate ability
Equilibrium: New innate ability
Equilibrium: Io always has bonus Outgoing Damage Amp which linearly scales with its health, reaching a maximum of 5% + 0.5% per level at 100% Health. At the same time, Io has Health Restoration and Healing Amplifications which also linearly scale with its health, but reach a maximum of 5% + 0.5% per level at zero Health
Overcharge: Now also provides 35/60/85/110 Attack Speed and 8/10/12/14% Spell Amplification to Io and any tethered Allies
Talents: Level 10 Talent Strength increased from +7 to +8
Talents: Level 25 Talent Relocate Cast Delay Reduction increased from 1.5s to 2s
1/22/2026
No hero-specific updates in this patch.
12/23/2025
No hero-specific updates in this patch.
12/16/2025
Base Strength increased from 17 to 19
Base Intelligence decreased from 23 to 21
Damage at level 1 unchanged (45–51)
Spirits: Mana Cost decreased from 100/110/120/130 to 90/100/110/120
Spirits: Cooldown decreased from 22/21/20/19s to 15s
Spirits: Duration decreased from 19s to 15s
Talents: Level 10 Talent +12 Attack Damage to Tethered Units replaced with +7 Strength
Talents: Level 15 Talent +60 Spirits Hero Damage replaced with +50% Spirits Damage
Talents: Level 25 Talent Unslowable during Overcharge replaced with -1.5s Relocate Cast Delay
10/2/2025
No hero-specific updates in this patch.
Patch 7.39dNet Gain
6/12/2026Spirits: Cooldown decreased from 26/24/22/20s to 22/21/20/19s
6/24/2025
No hero-specific updates in this patch.
5/29/2025
No hero-specific updates in this patch.
Patch 7.39Net Gain
6/12/2026Removed Sight Seer innate ability
Wellspring: New Innate Ability. Passive, can't be leveled up
Consumable items and item abilities that restore Health and Mana over time affect Io twice as fast. Total amount of restored health or mana remains the same
This applies to Healing Salve, Tango, Clarity, Bottle, Urn of Shadows, Spirit Vessel, Pollywog Charm, and Mana Draught
Example: Usually Clarity restores 150 mana over 25s. For Io it will restore 150 mana over 12.5s
Spirits: Aghanim's Scepter Movement Slow increased from 15% to 25%
Relocate: Cooldown decreased from 100/90/80s to 90/80/70s
3/27/2025
No hero-specific updates in this patch.
3/4/2025
No hero-specific updates in this patch.
Patch 7.38Net Gain
2/19/2025Base Damage increased by 7
Damage at level 1 increased by 4 (from 41-47 to 45-51)
Strength gain increased from 2.7 to 3.0
Damage gain per level decreased from +4.2 to +2.8
Damage at level 30 decreased by 46 (from 192-198 to 146-152)
Tether: Upon casting Tether, Io now has a buff that shows Tether's remaining cooldown. This buff is only visible to Io and Io's allies
Tether: Enemy Move/Attack Slow increased from 10/20/30/40% to 15/30/45/60%
Tether: No longer deals 15/25/35/45 Damage per second to enemies by default
Tether: Now upgraded with Aghanim's Shard
Tether: Deals 120 damage per second to enemies touching it. 50% of the damage dealt heals Io. This is considered a pseudo-lifesteal
Overcharge: No longer upgraded with Aghanim's Shard
Talents: Level 10 Talent +15% Tether Enemy Slow replaced with +1.5s Overcharge Duration
Talents: Level 25 Talent +400 Health to Tethered Units replaced with Unslowable during Overcharge
11/20/2024
No hero-specific updates in this patch.
10/3/2024
No hero-specific updates in this patch.
8/28/2024
No hero-specific updates in this patch.
8/14/2024
No hero-specific updates in this patch.
7/31/2024
No hero-specific updates in this patch.
6/25/2024
No hero-specific updates in this patch.
6/6/2024
No hero-specific updates in this patch.
5/27/2024
No hero-specific updates in this patch.
5/23/2024
Tether: Damage per second increased from 10/20/30/40 to 15/25/35/45
Tether: Enemy Move/Attack Slow decreased from 15/25/35/45% to 10/20/30/40%
Spirits: Creep Collision Damage increased from 10/15/20/25 to 12/18/24/30
Talents: Level 10 Talent Attack Damage to Tethered Units decreased from +15 to +12
Talents: Level 15 Talent Tether Movement Speed decreased from +6% to +5%
Talents: Level 15 Talent Spirits Hero Damage increased from +55 to +60
Talents: Level 20 Talent Relocate Cooldown Reduction increased from 25s to 30s
Talents: Level 25 Talent Attack Tethered Ally's Target now applies a 25% damage penalty on Io's attacks
3/21/2024
No hero-specific updates in this patch.
2/22/2024
No hero-specific updates in this patch.
12/21/2023
No hero-specific updates in this patch.
6/12/2026
Tether: Now deals 10/20/30/40 damage per second to enemies caught in the tether. Tick rate: 0.5s
11/21/2023
No hero-specific updates in this patch.
10/5/2023
No hero-specific updates in this patch.
9/9/2023
No hero-specific updates in this patch.
8/15/2023
No hero-specific updates in this patch.
8/8/2023
Overcharge: Aghanim's Shard no longer grants bonus spell amplification
Overcharge: Aghanim's Shard now grants 30% slow resistance
7/13/2023
No hero-specific updates in this patch.
6/16/2023
No hero-specific updates in this patch.
5/14/2023
Base Damage decreased by 3 (Level 1 damage increased by 2)
4/26/2023
No hero-specific updates in this patch.
6/13/2026
Now is a Universal Hero
Base Damage decreased from 13-19 to 7-13
Strength gain decreased from 3.0 to 2.7
Damage on level 1 decreased by 6 (from 45-51 to 39-45)
Damage gain per level increased from +2.7 to +3.6
Spirits: With Aghanim's Scepter the ability can now be activated to explode the spirits, after which they begin spawning again. Cooldown is decreased by 50%. Cannot be activated if the ability is on cooldown