Broodmother has always been a very situational hero. In the professional scene, there was a period when she was an automatic ban against certain teams and a very strong finishing pick. She absolutely destroyed weak safelanes, could be a situationally strong mid and could completely take over the game if she wasn’t countered during the drafting stage.
7.07 significantly changed the hero, yet her role and general playstyle remained somewhat similar. As a result of these changes the hero became less niche and as such is currently less punishing, but more consistent. This consistency is a double-edged sword for the pub players, especially at high MMRs: on one hand there are now more ways of dealing with hero without a specific draft; on the other, Broodmother became slightly more popular and we definitely see her more frequently.
Broodmother is at her best at the extremes of MMR range: her highest win rate is in 5k+ games, sitting at an exact 50%, while her second highest is in below 2k bracket. In her current form she is good at punishing weaker players and is also consistent in the hands of excellent players.
The hero is also at her best in the mid lane, having a 6% win rate advantage over her most popular role in the offlane, which was her historical position. Losing invisibility was a big hit for the offlane Broodmother, since she can no longer drain economy from supports in lane and almost guarantee her safety. At the same time, increase in the flexibility of web placement allowed the hero to be more mobile and pressure more than a single lane.
This is the explanation for hero mid lane advantage: current playstyle allows her to farm most of the camps situated around the midlane, get an economic advantage and then become a global threat on the map, as opposed to simply tying down a hero or two to a lane.
Additional argument in favor of midlane Broodmother is the popularity of double mid lanes. Broodmother is only ever seriously threatened in a 1v3 and theoretically should escape from almost all 1v2 situations alive. On top of it, the XP disadvantage of a dual lane is big enough for Broodmother to be able to apply significant pressure from level 3-4 onwards on the enemy mid support, either getting extra kills, or changing the matchup to a temporary 1v1 where the enemy is of a lower level. There are only a handful of heroes who can 1v1 Broodmother and all of them require a certain degree of execution to be actually effective.
Despite her lane dominance, Broodmother is far from being a hard carry. She scales relatively well, but is heavily outclassed DPS-wise in the later portions of the game. As such she should generally be played as a tempo hero with a heavy focus on map control.
Farmed Broodmother from the midlane is capable of standing her ground against two heroes at almost any stage of the game and can pressure the lane very well if her presence is left unanswered. This is how the hero is generally played in the professional scene right now: she can create space of her own in the early game, get one or two core items and then start pressuring the enemy team, while her own team is either farming up or supporting her in ending the game.
In teamfights her role is less about dealing damage and more about being disruptive: by simply attacking the enemy core, she can significantly decrease the enemy damage output, while the true position one focuses other heroes down. Alternatively, with an early Orchid build she can focus down an enemy support, while staying relatively safe with the help of lifesteal.
Being a tempo hero she generally wants to close the game relatively early, or focus on creating space for the allies and as mentioned previously, given a good enough start, she can excel at both.
Map control is extremely important for Broodmother: she wants to take as much space away from the enemy, while retaining control of her own jungle either for herself or for her position one carry.
The hero is also extremely flexible at breaching highground, capable of moving between lanes extremely fast. This generally means that she is at her most comfortable when at least two sets of outer towers of the enemy are destroyed, as she can poke several lanes at the same time, cutting waves and slowly wearing down the objectives.
Being able to freely move inside the enemy base allows her to either zone out the enemy supports from the sides of the highground chokepoints or initiate on them, potentially coming victorious in these situations or creating enough space for her team to follow-up. It is also the reason Blink Dagger is becoming a very frequent pick up on the hero, despite an already high mobility: you can blink into the enemy territory and already have an escape plan prepared.
The hero thrives on gaining map control and momentum, but is at a massive disadvantage when she loses map control herself. Without the outer towers she is a lot less safe in her own jungle as well as when taking the enemy neutrals. When playing against Broodmother, concentrating on map control should generally become a priority.
She is also quite weak in earlier 5v5 teamfights, only offering a nuke and her own right-clicks, which at this point will rarely apply the debuffs. Without the army of her spiderlings, her damage output is also very low, while lifesteal isn’t as effective without a decent amount of damage. The time Broodmother spends farming up in the early game should be exploited as much as possible to prevent her from snowballing out of control.
It is also worth noting that the new Spiderling and Spiderites have significantly lower HP pools and higher armor, meaning that while their EHP have stayed relatively the same, pure damage or cleave can destroy them extremely fast.
Broodmother’s role in the game has changed drastically as a result of 7.07: she is still a niche pick, but situations when she is good are a lot more frequent. She is also easier to deal with without the counterpicks, but require more responsive attention.
The hero is far from being dominant in the pub scene, but she is still a rare, but consistent pick in the professional scene. Trying to make her work will generally require a certain degree of coordination in pubs, but when playing a non-solo game she can be a good hero to train: she is unlikely to win the majority of your games, but will definitely provide a much deeper understanding of lane momentums and map control concepts, as she is very dependant on both.