Week 9: Where did he go?
Wards, fog and detection — the one resource you spend on so that a decision you have not made yet will be better
3 May 2027
This week’s decision#
The most common sentence in a beginner’s game, and it is not really a complaint about the enemy. It is a report about a resource you chose not to buy.
The mistake this week fixes is warding at your own feet — or never looking at the minimap and still pushing two minutes after all five enemies vanished from it.
Mechanics#
Fog. What you cannot see is still happening. Dota’s default state is that you do not know, and everything in this week is an attempt to buy your way out of that default for a while.
Observers buy vision; sentries buy the denial of the enemy’s vision. Beginners routinely treat these as one item with two names. They are opposite purchases.
Detecting invisibility. Not everything you cannot see is hidden by fog, and the two problems have different answers.
Minimap habits. Glancing at the minimap on a rhythm is a trainable action, not a talent some people are born with.
Pings. Turning what you can see into what your team knows, at no cost whatsoever. The cheapest thing on this page.
The resource lens#
Information is the cheapest and the most expensive resource at once. A ward costs almost nothing; the death it would have prevented costs a great deal of gold and a minute of the game. What makes it hard is that missing information gives you no signal that it is missing — you find out at the moment you die.
Before the lecture#
Valve’s in-game tutorial, section 2 — map vision; and section 3 — detecting invisibility.
This week’s hero#
Vengeful Spirit — Wave of Terror. It grants vision as a side effect, which makes it the classic case of an ability doing two jobs while a beginner sees only one of them. It leads directly into a habit worth keeping: an ability’s value is not only its damage.
This week’s item#
Observer and Sentry Wards, taught properly this time. Week 4 used a ward to block a camp and promised the rest for later; this is later.
Why here rather than back in week 4: a ward is only worth what you know about which parts of the map matter, and that only holds once you understand waves from week 3, the jungle from week 4 and positions from week 6. Warding well is downstream of nearly everything else in this course.
After this week you can…#
- place a ward in a bot game with a stated purpose
- say where an enemy probably is when they disappear, instead of continuing to push
- say what an Observer and a Sentry each bought you
Teaching team
- Wen "Courier" Adeyemi — convenor