Roshan Timing and Aegis: Patch Rules, State and Conditional Odds

Roshan timing: separate game state from a probability estimate

A team takes Roshan while trailing in gold. That changes the position, but it does not supply a universal increase in match-win probability. Check who received the items, what the team can do before they expire, and what the opponent can still defend. A price decision needs a probability estimate and an executable quote as well as an account of the objective.

This guide separates dated game facts from hypothetical calculations. It supplies no measured “Aegis uplift” dataset and makes no claim that a specific operator systematically underprices Roshan. Numerical probabilities below are assumptions used to demonstrate the calculation, not observed professional win rates.

Use the map for the event's patch

Checked 2026-10-30: Valve's 7.38 notes moved the pits back to the river. 7.41 switched Roshan's pit preference and initial spawn to the top pit. The 7.33 corner-pit layout is historical, not a current navigation rule.

Read the active pit on the minimap and verify the event's patch and actual day/night state. Do not infer current access from an old “Radiant day corner” label. Hero effects, travel during a transition and information available to the observer can make a clock-only description inadequate. Describe the observed position and the timestamp first; use any cycle model only under stated assumptions.

For example, 31:00 lies in the daytime part of an assumed cycle with day at 0:00 and alternating five-minute phases. Calling that time “night” is inconsistent with that assumption. It still does not identify a pit without the applicable patch and actual state. A correct remainder calculation cannot repair an obsolete map.

Then examine approach routes, surviving towers, vision, visible heroes and possible rotations. An objective being closer to one side does not award it to that side. If a carry is across the map, record that observation without converting it into an automatic upset probability. Distinguish a verified missing defender from a hero who is merely unseen on the broadcast.

Respawn uncertainty is conditional on your information

Valve's documented respawn range is 8 to 11 minutes after death. Record the death timestamp and inspect the available timer or vision information. A range is not an exact spawn time, and a rule about what one observer knows is not necessarily a rule about what both teams know.

For a planning model only, suppose the unknown respawn is uniform over the 180-second window and no newer information is available. If death was at 26:10, the window is 34:10 to 37:10. At 35:40 the model assigns 90/180, or 50%, probability that respawn has occurred. This distributional assumption describes the calculation; the time range alone does not prove uniformity.

The conditional calculation requires evidence that Roshan has not respawned at 35:40. A camera that has not shown the pit does not establish that. If an ability, timer or direct observation supplies more precise information, use it rather than the uniform approximation. Rechecking state is more useful than increasing confidence in an assumption that has already become obsolete.

Keep game time and observation time separate. A delayed stream can show a valid past state while a betting quote reflects a later one. The absence of a kill on your screen does not prove that a market remains open or that the shown state is current. Record the quote actually accepted, including any price change or suspension.

Track the actual reward and its holder

Do not reuse a fixed 7.33 reward table. Valve's 7.38 notes removed Aghanim's Blessing from Roshan's drops. Check the drops and holder in the actual match rather than inferring an extra item from a remembered kill-number rule. Item effects and rewards must be read against the event's patch.

Valve's current Aegis data gives 300 seconds before expiry and a five-second reincarnation delay in the standard mode; Turbo has a separate duration. Record the actual pickup time and whether the charge has been consumed. A five-minute duration does not mean five minutes of guaranteed attacking advantage.

Ask whether the holder can deal building damage, survive after reincarnation and receive support. Check nearby allies, defensive cooldowns, access to the base and whether an important defender is alive. An item on one hero does not provide a second life to the entire team. A successful Roshan kill also does not prove that the team will immediately push.

For any other reward, record its identity and current effect. Do not assume every cooldown-reset item also refreshes items, or describe healing as an additional resurrection. Those shortcuts can turn a plausible fight description into an incorrect state model. Where the inventory or relevant cooldown is unknown, keep that input unknown rather than assigning the strongest possible combination.

Price a hypothetical state without inventing an uplift

Suppose an analyst explicitly assumes a post-Roshan win probability of 0.79, and the available decimal odds are 1.38. Conditional on that probability, expected net return is 0.79 × 1.38 − 1 = +9.02%. The fair price under the assumption is 1/0.79 = 1.2658. The arithmetic does not validate the 0.79 input.

If the probability were instead 0.62, the same quote would give 0.62 × 1.38 − 1 = −14.44%. Break-even is 1/1.38 = 72.46%. The difference between these examples shows why an uncalibrated fixed addition of 20 percentage points can dominate the decision. Do not add that number merely because the Aegis icon appeared.

To estimate a repeatable effect from data, define a population, patch range, observation time and outcome. Record gold, levels, objectives, draft, surviving structures, buyback availability and the holder's state. Evaluate on later matches not used to choose the model. Teams that secure Roshan may already be stronger; the difference in their win rate is not automatically the causal value of the item.

The related comeback probability model and our net-worth model guide describe model structures. They do not independently certify a measured Aegis effect for this article. The useful comparison is a model with explicit inputs and uncertainty, rather than an unexplained percentage presented as telemetry.

Keep objective markets and match markets separate

“Next team to kill Roshan” and match winner are different events. A team can secure the objective and lose the game, or lose the objective and defend successfully. Read how the market defines the killer, whether an Aegis steal changes settlement and how interruptions are treated. Do not substitute item pickup for a kill event without checking the contract.

Likewise, a draft that can kill Roshan quickly need not be strong at contesting an occupied pit. Record damage, available abilities, opposing vision and the risk of being interrupted. The objective and kill-market guide provides related market distinctions; none supplies a fixed conversion from one event to another.

A map-win estimate can be used as an input to a series model only with the other map assumptions made explicit. The series calculator combines supplied map probabilities; it does not derive those probabilities from a Roshan event. Avoid counting the same positional advantage once in the current map estimate and again as a separate series bonus.

Keep a state log that can be checked later

For each observation, save event, patch, game time, visible pit, death and pickup times, observed items, holder and source delay. Add the market definition, both available prices where applicable, accepted quote and stake. Distinguish observed, assumed and missing inputs. Preserve losses and failed objective attempts as well as memorable successful takes.

Check the outcome after settlement and compare predictions against results in a later evaluation set. A convenient sample size does not guarantee a stable uplift estimate: dependence between observations and changes in patch or selection process matter. Report uncertainty and failures, not just a profitable subset. A useful review asks which observation changed the probability estimate and whether that change was justified.

Use the Dota 2 evaluation guide for the broader state checklist. Roshan is one part of that state. Confirm the applicable rules and current information before interpreting the price; the objective itself does not establish a betting advantage.