Time to get First Blood
You are starting to feel comfortable in the lane, you have imposed your dominance, your lair is established your babies are burgeoning, its time get get first blood.
This is where brood becomes really mean, it should happen by level 3 or 4 but you will have a good 10 or so spiderlings. It's quite simple at this point. Begin sending your army at the enemy.
Try not to do so where they will draw enemy creep aggro. You don't have to commit for a kill everytime. Sometimes its good to get chip damage on them and draw them out. But the idea is to surprise the enemy with the amount of damage your broodlings can lay down on them. So wait until you have 8-10 spiders. Your best bet is to start your army directly behind the hero (only works if they don't have vision of course) Their natural instinct is to run backwards
Prior to the 6.82 patch it was easy to surround the enemy with your brood army. Now the broodlings have this weird habit of clumping all together in one tiny unit. This has some advantages though. It actually makes them easier to use for those who don't have RTS practice in enemy trapping. Since they can all hit at the same time for fully effective DPS. Rather than tripping over one another.
If they have a hero like Lina with an AOE nuke you want to try to bait this out before committing. Sometimes splitting your army in half is a good way to do this. Immediately after casting their nuke you should move in with your entire army. Of course if possible try to avoid the first nuke. These spiders are now super-fast so you can do it.
Tip on Microing with Brood.
Of course everyone is different but I my preferred method is to have brood momma herself in control group with the 1 key. I actually dont have her spiderlings in a control group since they die so quickly its hardly worth it. What I do is use the lasso method to control them. (Click drag your mouse to get all your units.) Then you send them at your enemy. And press the 1 key to separate the brood momma from the pack and hold her back if need be.
You as the brood mother don't even have to get your hands dirty when running at the enemy heroes, your right clicks help of course and if you feel it's safe join your children do it. But the best part of brood is that to ensure a kill you rarely have to expose yourself.
What I will do is hide in the webs on the outskirts of the tower and try to get in the finishing blow via a my nuke.
Enemy heroes will often juke in the grove of woods above their tower where they are protected by fog of war and the tower damage. When you are sending your broodlings at them you are going to have to redirect them because they will stop when getting fog of war juked. Simply A-click them in the general direction the hero ran. They will swarm in there and seek him out. Also place a web there so they can phase over trees and move faster. You can also join them back there most times pretty safely.
Sometimes the heroes will make it pretty far away from the tower back towards there base, a chase here is not always bad, you can lay webs deeper into enemy territory to make your spiders move faster and potentially get the killing blow with your nuke. This is a risky maneuver and you might get punished for it, so be careful.
Brief Item Build discussion.
I am not going to discuss absolute must have items beyond Soul Ring. I have tried so many different builds for brood and many of them are quite successful. Prior to the 6.82 patch I would make Sange and Yasha 95% of my games. But with the added speed bonus I am not as hot on this item anymore. I will however talk about items I like and why.
great versus Slark, AM, Faceless Void, Ember Spirit, QoP, Puck, basically anything squishy with an escape. If I do Orchid I try to get this within the first 15 minutes or not at all since it has diminishing returns.
Radiance/Hand of Midas
the uber greed build. If you are absolutely dominating your lane and knocking down towers, owning their jungle these are definite considerations. Again I cant get the radiance in the first 15-20 minutes I do not bother. Prior to 6.82 I was super hot on the Midas too, mainly because between the solo off lane exp, easy kills and jungle camp, I would often out level everyone in the entire game, including the mid players. And Midas made that happen even faster. However, with the new bounty changes being, a uber high level with a nice streak is a huge liability now.
great item on brood compliments her chase play style quite well, also some smart enemies till tp out when you engage on them, Brood is much like Blood Seeker in that regard.
Huge crits, quick burst, good synergy with ult. I am quickly learning to love this item on brood.
I build treads on Brood 98 percent of the time. SometimesI will go Boots of Travel, for split push fun. And even more rarely I will get Arcanes, normally when going dagaon/e-blade.
Great vs. PA and Faceless void now especially with the 6.82 change. Between your miss orb and this you are able to go toe-to-toe with just about any hard carry. That is until they get smart and buy an MKB/BKB.
Probably one of the most important items on Brood who needs to carry. I would say after Soul ring this is the second best item on Brood. When you pop your ult and your bkb together, you can manfight even with 3 or 4 enemies on you, since your lifesteal is so high.
again if you are roflstomping your lane and they are team full of squishies this is well worth it. Esp. good against pugna, and tinker that use decrep or ghost scepters, as well as PA with her annoying evasion,(dodge this!). You might also need an orchid to support the intense mana cost this entails. I call this the clown build when you feel like the game is totally getting out of hand use this build to finish it and for funsies.
I think is very situational on brood. Sure it helps you push and gives you lifesteal, but you are not always with the team so it does not benefit them that much. I do not often go this item. But I see its merits.
One of my personal favorite items, helps brood in all the right places, great pushing item, helps her right-clicks and buffs her babies.
Good against nuke heavy lineups/burst teams. If it buys you enough time to recover and turn on your ult it will let you turn the fight around.
Great for breaking Dust. Pretty big investment though. I consider this a must versus Slardar and Bounty Hunter though, often as your first big purchase.
I know people are in love with this item. I know it can help you split push. But I feel it has gotten nerfed pretty hard over the last few patches. Its still a nice item, but the cooldown is long, it really falls off late game and can actually feed the enemy. If you have a super push focused lineup like a furion, DP, Lycan. Then this is a good pickup, as you first big item. I will also get it for techies and other stealth units for obvious reasons. But I find myself going this item lately only about 1 in 10 games. Maybe its because it does not compliment my play style. Brood can be a rat there is no doubt, but with necro book, you lose some of your manfight/pick-off potential that another item could provide.
this is a situational item, but against very evasive heroes like Storm Spirit, ember and void I think its a nice add.
I mentioned my clown build and my super greed build that i show above, the last build is when they really hate you, sometimes you are going to get an Axe, LC and Earth Shaker against you. Cuz let's face it people hate spiders, S and Y is always a nice pick up on Brood and is easy to build since its most expensive component is 1k gold. BKB is also great since its most expensive component is 1.6k These might help you turn around a game where you did not start off too hot.