When I started playing PoxNora UD Spiders was the first good BG I built and having played it for a few years I feel like I can speak intelligently on it and give some recommendations on how to build a good spider deck. What's so great about Spiders? Spiders can attack the opponent for great damage like any good Underdepths BG but they stand out in their ability to deftly climb over any terrain (by round 3 or so), global multiattack, and their ability to swarm the enemy. Spiders swarm so well that I consistently see surge units hit play at 30-40 damage. In addition spiders have the good fortune of being very cheap to build, the critical champs are mostly non legendary. The legendary for spiders, unlike some thematic legendaries, isn't at all necessary for a fully functioning thematic build (unlike say Lonx Chieftain or Snaptooth Chilan). This makes it a great deck for new players to try and build. What's the catch? If the enemy deploys something with sever summons things can get sketchy and Spiders are certainly susceptible to AoE Spells, X Blast abilities, Cone Attack Abilities, or anything with good Crowd Control (looking at you Draksar Ravenspeaker). To fight these you need to understand how to properly position yourself to mitigate the damage caused by these counters. If your opponent plays something with Sever Summons you'll have to rely on your quality real champs to get a kill on it and start rebuilding your spider empire from the ground up again. Although, if you know you're opponent is using a sever summons champ you can choose to leave your spiderlings near your shrine (which is where most of them will start anyways). In addition you may be concerned with the lack of detection. None of the spiders themselves have detection. For these elements you will need to include some other champions from within UD. Finally, Spiders are weak to Zombies. That's a fact. They can swarm the spiderlings to make more festering corpses. Against Zombies you need to avoid playing Protect the Nest and that makes Spiders so much less effective. What might a Spider BG look like? Generally you need to be running 2x Broodmothers, 1x Kl'zik, 2x Protect the Nest, and probably some other good spiders which I'll cover in detail in the next section. My current list looks like this, or you could try a slightly more budgeted deck. My build makes a point of just running spiders so that it can play superiority (because I don't have to worry about hitting my own spiderlings). However, if you remove the superiority for something like Fire Blast you can run some other runes from UD that fill some of the BG's gaps like adding another ranged unit with Grimlic for example. Additionally, I like to run Retribution but Sacrifice is also a good choice for that slot. Many people far prefer sacrifice but I definitely think that Retribution is better. I'm certainly the minority, I may just be bad at this game, but that's my personal choice. Pick whichever works for you, but I strongly recommend one or the other. How do I play them? Most games I play with spiders involves opening with a decent fontrunner, Phase Spider is easily the best at it but just about anyone can suffice except for Broodmother. Broodmother makes an excellent turn 2 deploy because then you're almost guaranteed to trigger Creep and Crawl on turn 3 which is usually the earliest you'll ever actually engage the enemy in a fight. Once you've got a basic army set up cast your protect the nests. It may not immediately appear to be the case but Protect the Nest is the best rune in any spider bg. Too many times I've heard people say that the only real threat in a Spider BG is Kl'zik but they are horribly mistaken. She's the biggest single threat with life siphon and surge and propagate forming a mean combo but the real threat in this deck is the hyper efficient generation of meat through Protect the Nest. If you have the warbanner out it becomes 30 nora for 15x6=90 HP of meat. That's a jaw dropping 3:1 ratio. Now this is over several turns which brings up my last point about playing spiders. Although you have the ability to just win out by steamrolling with a Kl'zik+Demon Shield sometimes or can shrine rush with Kl'zik stealthed by Nightfall, 9 times out of 10 Spiders play a game of attrition and win through constantly recasting Protect the Nest for the efficient and consistent meat coming out of the shrine. An additional note. The Spider's early game is like most UD decks, you deploy high damage units that get in the enemy's face and apply some early game pressure. Unlike most UD decks Spiders have the option of retreating if the enemy pushes back too much and letting the spiderling army catch up. Now your front line has at least doubled in size and you can start pushing back again. In most of my games if the opponent forces me to retreat into this strategy although it may take a while I will usually be pushing towards my opponent enough to slowly gain ground until I'm at their shrine.