Introduction
“Beep, boop, beeeeeep.”
Io, better known to long-time Dota players as Wisp, and still more commonly referred to as Wisp in general, is a strength support hero with a global ganking presence who is typically partnered with a single hard carry to deliver one of the scariest ganking combos in the game.
Io's complete character profile can be found here.
Pros & Cons
Pros
- Global ganking presence after level 6
- Provides incredible steroids to an allied hero
- Combines superbly with specific carry heroes
- Fantastic source of healing and mana regeneration for your carry
- Can help allies tank insane amounts of damage
Cons
- Good communication with the carry you’re going to be supporting is an absolute must
- Only suitable for certain line-ups
- No longer has any stun or form of lockdown
- Poor use of relocate will get yourself and your teammate killed
- Only has one damage-dealing ability
- Very low win-rate in public matchmaking – the second lowest out of all Dota 2 heroes
- Squishy
Item Build
Io/Wisp is perhaps the most unique support in the entire game. This adorable ball of light is best described as an enabler. By itself, Io is a terribly under-powered hero that is nothing but a burden to the team it’s on – squishy, weak, with only one damage-dealing ability, low damage output and absolutely no stuns or lockdown. Partner Io up with a handful of specific carries and communicate well with your teammates, however, and Io transforms into one of the most over-powered strategies ever developed in Dota thanks to its global ganking presence and the buffs it provides to its chosen partner hero.
It is entirely because of these strong contrasts – a weak hero with no damage output and no lockdown, but one which can make a team composition utterly overpowering so long as the team communicates well – that Io is both one of the least played heroes in public matchmaking with the second lowest win rate out of all of the heroes in the game but at the same time one of the most frequent bans in competitive Dota, consistently consider a tier 1 hero who has an extremely high win rate.
In short, if you have a mic and a friend you trust and communicate well with, then Io is often a source for convincing victories. If you don’t have all of these then Io becomes a very questionable pick-up.
Starting Items
Io’s job is, essentially, to shadow and support a carry. The most frequent and popular partner carries for Io are Tiny, Chaos Knight, and Sven, but any carry that benefits greatly from high mobility and attack speed boosts makes a viable partner.
In the laning phase your task will typically be twofold: 1) To support the carry you’ll ultimately be ganking with, making sure their lane is safe, their farm uncontested, and the opponent gets very little out of the lane. And 2) To stack jungle camps, pull the creeps if the situation demands it, and get your level 6 up and running as quickly as possible without leeching from your carry.
A typical starting item set-up for Io will look like this:
- Courier and/or Observer Wards, Tangos, Healing Salve, 1x Gauntlets of Strength, Iron Branch.
This gives you good regen, which you’ll be able to pool to your carry if necessary, or burn through yourself if you need to harass the enemy offlaner. The Gauntlets and Iron Branch give you a nice chunk of starting stats and both will prove useful later on.
Early Game
Upgrade the Courier into a Flying Courier at the 3 minute mark, and continue to buy Observer Wards whenever they come off cooldown.
In the early game you will definitely need: some basic Boots of Speed and a Magic Stick (which you can upgrade into a Magic Wand along with the Iron Branch you started out with).
You should also upgrade the Gauntlets of Strength into something. Your options here are a Bracer (some value stat gain) or an Urn of Shadows (regeneration and burst heal/offensive damage over time nuke to finish off fleeing enemies).
An optional, but highly recommended item, is a Bottle. Bottle, when used on an Io that is tethered to any allied hero, effectively grants twice the regenerative effects, making it a very efficient item to purchase on Io. For the regeneration to pass onto the allied hero Io must not be at full health or mana, however this is easy to achieve simply by triggering her third ability – Overcharge – so you will always be able to heal and replenish an allied hero’s mana pool as well as your own if you have some Bottle charges.
Core Items
As far as upgraded boots go, Io has a lot of options. Power Treads will give you so much-needed health, Tranquil Boots will give you high health regeneration, which is a strong option if you struggle in the early game and face almost constant harassment, or Arcane Boots, which are highly recommend if you build your team’s Mekanism so you have the mana to cast it as well as you other abilities liberally.
Mekanism is your priority core pick-up. If there are no more viable Mekanism carriers on your team that will get it up much faster than you (such as a mid Viper, or a jungle Chen), then Mekanism should be your go-to core item. Be sure to check with your team to see if anyone else intends to build one before you get started on it though.
Luxury Items
Drums of Endurance – Drums of Endurance are a great option because they give your team (and the carry you’re tethered to) bonus attack speed and move speed auras, whilst at the same time giving you plenty of stats and being easy to build into (since the components are so cheap you can buy them up whenever you have the spare unreliable gold, meaning you won’t lose much gold when you die).
If already have a Bracer from the early game then Drums become a natural extension to your inventory. If you, however, someone else on your team (in particular the core(s) you’ll tether to) already have Drums then they become a less valuable pick-up and you should probably consider a different luxury item.
Vladmir’s Offering – Yes, you’re ranged, so you won’t get the lifesteal bonus from Vlad’s, but you’re not buying it for yourself, you’re buying it for your team. Vladmir’s Offering is great to pick up on a support even if your team doesn’t consist of any melee heroes because of the bonus damage and armour it provides. If your team does have a melee core and no one else has purchased one then it’s an excellent utility item to purchase.
Ghost Scepter – The go-to luxury pick-up if you find the enemy team is able to bring you down quickly with physical damage (typically in the form of right-clicks). It’s especially recommended on Io because the nature of your skillset means you’ll likely be attacking behind enemy lines and thus putting yourself in greater danger than supports are accustomed to.
Ghost Scepter will buy you a clutch 4 seconds of physical immunity, which gives you time to create distance between yourself and the enemy carry (possibly using Relocate or by Tethering away) or at the very least buys your team 4 seconds of distraction time.
Black King Bar – An expensive but potentially game-changing item. Io is often a high priority target – not only will you often be the focus of enemy attention once you Relocate into an engagement, you’re also squishy and easy to take out, being highly susceptible to burst magic damage and stuns. Black King Bar will allow you to avoid being insta-killed by burst magic damage and make it impossible for the team to lock you down. You also get some nice health gain from it.
Heaven’s Halberd – A fantastic anti-carry item, thanks to the ability to disarm an enemy core for 3.0-4.5 seconds, Halberd will also give you a much-welcome chunk of health and evasion, making you a lot less fragile.
Force Staff – Force Staff gives you less all-round stat gain than an item like Drums or Heaven’s Halberd, but it gives you much more mobility and more direct team utility (Drums’ auras are largely a passive, somewhat unnoticeable buff). It’s an amazing escape tool for someone who is naturally very squishy and can be used on allies and enemies, making it a great play-making item for clutch saves or to Force an enemy into bad positioning.
Heart of Tarrasque – The ultimate luxury item for Io, but one you’re unlikely to ever be able to afford. Gives you a huge health boost and will make your healing effects from Tether insane. You also won’t need to worry so much about harming yourself from Overcharge usage, as Heart almost halves the negative effects from Overcharge to Io.
Shiva’s Guard – The second of three ultra-expensive options for Io. It gives you utility for the team, thanks to the AoE Arctic Blast and slow aura for enemies, gives you a nice chunk of armour to increase your tankiness, and will give you a big intelligence boost.
Scythe of Vyse – Another item you're unlikely to be rich enough to ever afford it, and if you are the game is likely already won anyway, but if the game is really stretching out it can potentially be a decisive item to get. 3.5 seconds of lockdown on a key enemy hero is the reason Scythe is considered one of the most powerful items in the game.
Situational Items
Sentry Wards, Dust of Appearance, Gem of True Sight – all-important detection. You’ll need at least one of these in your inventory if the enemy line-up features an invis hero. Sentry Wards will also allow you to deward rune spots, and Gem will give you superior vision going into the mid and late game.
Medallion of Courage – A really good cost-effective early game support item. The mana regeneration will help a lot and the minus armour is seriously under-estimated in public games. Also opens up the possibility for an early Roshan for your team.
Pipe of Insight – A very expensive item for a support, and not an ideal pick-up if you bought the team’s Mekanism (having both on one hero is very risky, especially a squishy one like Io), but always a good item to have if the enemy team has any magic damage (which they almost certainly will). Quick rule of thumb: go for it if you didn’t buy the Mekanism earlier.
Necronomicon - Great if you’re part of a pushing line-up or your team is struggling to break the base. Also a great item for teamfights and for countering any invis enemy heroes.
Skill Build
Tether is a unique ability which allows Io to link itself to an allied hero or unit. It is always skilled first but, since its nerf in patch 6.79, maxed last. From up to 1800 units away, Io can latch onto an allied unit for 12 seconds. During this time both units receive a 17% move speed boost and the other unit receives 1.5x any amount Io is healed or mana regenerated for during this time.
The Tether has a maximum radius of 900 units (exceed this and it will break), and any enemy units that come into contact with the link are slowed by 100% for 0.75/1.25/1.75/2.25 seconds. Before patch 6.79 the Tether used to stun, which made it worth skilling, but now only the slow scales with levels and so it is left at level 1.
Spirits is Io’s only damage-dealing ability. It is usually skilled either second or last but is maxed first. It triggers 5 orbs of light that travel in a circle around Io. These orbs each deal 8/14/20/26 magic damage in a 300 unit AoE whenever they hit enemy creeps, and deal 25/50/75/100 magic damage each to enemy heroes they come into contact with. When hitting enemy heroes they also explode.
The Spirits last 19 seconds, unless they come into contact with enemy heroes, in which case they explode and are lost. The ability has a 20/18/16/14 second cooldown, so in theory once you have at least two levels in Spirits you can constantly have them triggered (again, unless they hit enemy heroes).
Once triggered, Spirits grants you access to two sub-abilities, which are mapped to the D and F keys on your keyboard by default. The D button allows you to bringing the Spirits in closer to Io, whilst F will cause them to travel outwards, although at all times their movement in a circle around Io is consistent.
Overcharge is a steroid ability that is skilled second or last but maxed second. It increases the attack speed of Io and any unit she’s tethered to by 40/50/60/70 and reduces the damage both take by 5/10/15/20%. However, this comes at the cost of 4.5% of Io’s current health and mana per second.
Overcharge effectively increases Io and the tethered unit’s health by 5.26%/11.11%/17.65%/25%, although for Io the health drain will cause this to rapidly diminish for her.
Relocate is a global teleportation ability. It is always skilled (levels 6, 11 and 16) and is considered one of the strongest abilities in the game if used properly. Relocate allows Io to transport both itself and any unit it is tethered to to any point on the map.
After a 2.5/2.25/2 second delay, Io and any tethered unit will be transported to the spot Io selects. Then, after 12 seconds, Io is returned to the starting point, bringing any unit she is tethered to back with her. This allows you to either bring the hero back with you, or leave them behind, giving the ability multiple uses beyond simply ganking.
Gameplay Tips
Tether can be used as a pseudo escape mechanism. Since you can tether a unit from up to 1800 units away, and doing so will immediately pull you closer to that unit by 300 units, you can Tether to a hero or creep that is approaching from relative safety in order to escape a dangerous situation.
| Remember: Tether doesn’t just work on allied heroes, you can also Tether to allied creeps for the speed boost. |
In order for the Tethered unit to gain the health and mana regeneration effects from Tether, Io must not be at full health or mana herself. If you are, then you can easily hurt yourself by activating Overcharge while using whatever regen it is you have access you.
| Note: The Tether can be broken in one of three ways:
|
Spirits, individually, deal fairly minor magic damage to heroes (25/50/75/100) but the total damage output of the ability is actually quite reasonable – 125/250/375/500 magic damage. Those still remaining at the end of the 19 second duration (or if it is re-cast) will automatically detonate, dealing damage in a 300 unit AoE.
| Tip: Spirits, although they no longer provide as much vision as they used to, do still provide vision if they collide with an enemy hero, so they can be a decent means of scouting tree lines and through fog of war (such as if your team needs to check Roshan but you don’t want to blindly walk into the pit). |
The difficult part about using Spirits is toggling their distance so that you hit enemies. This can, when starting out with Io, be quite the distraction. Don’t lose sight of your more important role of staying alive and protecting/buffing your team’s carry. If necessary simply keep the Spirits at their default distance until you become familiar with the hero enough to control them without losing focus.
| Warning: Unlike most other abilities in the game, the Spirits are visible to the enemies even if Io herself is invisible, so be careful if activating an Invisibility rune not to give your position away by pre-casting Spirits. |
Remembering that while using Overcharge you drain your own health and mana substantially – by 4.5% per second – so only activate it when you or the carry you’re Tethered too is about to, or is currently taking, substantial damage. Although you cannot die from Overcharge, it can bring you extremely low on health, making it easy for the enemy team to finish you off.
Although the mana and health drain may put you off using Overcharge, you shouldn’t let it put you off. 20% incoming damage reduction is not to be under-estimated, and if you or an ally you’re Tethered to become the focus of enemy attacks you should always use Overcharge.
Relocate’s most obvious use is as a global ganking tool. You can turn what would be a 1 on 1 engagement on the other side of the map into a 3 on 1 engagement in just two seconds, which makes effective use of Relocate almost game-breaking (and hence Io’s high pick/ban rate in competitive Dota).
Relocate is also frequently used to teleport an allied hero who is about to die out to the safety of the Fountain, then either leaving them at base or bringing them back into the battle with full health.
Just remember that if the fight is absolutely lost and bringing a teammate with you will only get them killed you should break the Tether connection before teleporting away.
Last Updated - Patch 6.82.
