Invisible heroes are a big hassle to early Dota players. They can come out of nowhere at seemingly any time, and even if you do a lot of damage, they can vanish without a trace. Here’s how you can stop invisible enemies.
Truesight items: Items that allow you to see enemies heroes. First is Dust of Appearance(180 gold), or just dust for short. When used, it causes the immediate area to have true sight for a short time. Next is sentry wards (200 gold). Like observer wards, you place them and the area near by has true sight. Last, is Gem of True Sight (850 gold), which automatically gives permanent true sight to the area around the holder. This is the best option for taking down enemy heroes, but keep in mind that when the holder is killed, the item is dropped, which means that the enemy can pick it up (but teammates can as well). You can also destroy the gem by attacking it, which can be useful if you have invisible heroes on your team. You can buy all these items from the base shop (you can use the search bar in the shop to find them quickly).
Silence: If they are silenced, they can’t cast spells and they can’t go invisible. Some heroes have silence abilities and some items have some as well. Keep this in mind if you see someone pick an invisible hero.
Abilities with True Sight: Slardar’s Amplify Damage and Bounty Hunter’s Track allow invisible heroes to be seen as long as you used the move on the hero when they were visible. Zeus’ ultimate also reveals invisible heroes, but only for a very short time.
Stuns/Burst Damage: Many invisible heroes can’t take a lot of punishment, so stunning them, which allows for more time to attack, or having skills that do a lot of quick damage can be ideal for harassing them.