Lab of Legends: Deck Building & Strategy Tips

Den is offering the most essential advice on how to approach the popular Legends of Runeterra PvE mode.

Hi everyone, den here!

Lab of Legends has been introduced several weeks ago and instantly became a huge hit. The concept is very simple: using one of the champions available in the Lab, you go to battle against a series of increasingly complex AI decks, built using Shadow Isles, Frejlord, and Piltover and Zaun cards.

In patch 2.5, new difficulty modes have been added on top of the default ‘Normal’ mode. We can now select how hard we want our challenge to be – ‘Hard’, ‘Heroic’ or ‘Legendary’!

This article is the guide to help you overcome the challenge that is the Lab of Legends. We’ll be talking about general tips, how to build your deck, and specifics of playing with each champion. We’ll be also looking to release more Lab of Legends guides, including the ones where I’ll go through the bonuses – like passives and items. Let us know if this is the type of content you’re interested in!

PvE modes usually are great to learn the game and work on the fundamentals, which is precisely my first point to start off this piece: look to play simple and efficiently.

Before getting into the specifics of this mode and the various strategies we can adopt, it seemed most important to remind you that you are playing against an AI. There won’t be any hand-reading going on, no need to think about how our opponent is going to assess the situation. After 2 or 3 runs, you will remember the most obvious patterns to play around and there isn’t so much else to do outside of it. The key to succeeding in this mode is to do the simple things right and build a deck that makes sense, which is what we will dive into now.

  • Deckbuilding for the snowball

Most of the time in Lab of Legends, we want to put buffs onto the same card. The reason we want to build our deck this way is that every time we buff a card, we also get some extra copies of said card added to our deck. These extra copies are the reason why we want to invest in a single card and maximize our chances of drawing it.

Mana-cheating items and passives are very powerful. This rule applies to both followers and champions. Obviously, keywords like Elusive, Overwhelm and Quick Attack are best since most of the wins happen through combat, so try to further invest in units with these keywords.

After your first bonus, you should have a clear idea of the kind of snowball your deck will be trying to achieve. Don’t be afraid to use the rerolls early in order to get a good start in that direction.

  • Playing for the ‘carries’

As we are building to get a huge threat online as soon as possible, we should also play in that direction during the games.

The mulligan should be aimed at finding this particular card and protecting it as much as possible. Then, our game plan should be to develop and protect it as early as possible – or to control the pace of the game if we don’t find it. Based on what our carry can do, our tactics should adapt accordingly.

With an Overwhelm unit as our carry, we will try to take advantage of small opposing units, so surround it with spells and Challengers (or give it Challenger directly) so we can control where our big boy will hit. With a Quick Attack carry, we will look to force situations where the opponent will have to sacrifice his best unit into our quick-attacker every turn. An Elusive minion usually doesn’t require specific support, just protect it from possible spells trying to remove it.

  • Zoe ‘god mode’

Sometimes, the game offers you Zoe as a second champion, and that usually is the sign of a great run ahead of you. Zoe in this mode does absolutely everything. She can be the carry if you boost her enough or simply give your deck some value that allows you to build towards a set goal. If you’re struggling in Lab of Legends, especially with champions that cannot carry the game by themselves, trying to find an early Zoe is a really easy way to get some wins.

Over time, you will amass enough knowledge about the contents and patterns of every AI deck, so your piloting will naturally get better. In this section, I’ll share a few valuable tips that you should keep in mind for particular key fights.

  • Think about if there’s a way for you to secure some healing before ending the fight if possible. The heal doesn’t matter in this situation in the boss fights (Thresh, Sejuani, Viktor), because you replenish your health to full after these encounters.
  • Against The Scargrounds, if the opponent attacks with a Feral Mystic on turn 2 and has some banked mana, it’s almost guaranteed it has is Elixir of Iron in their hand. With this deck, AI will usually play only one unit per turn so going wide is a good idea.
  • Against Sejuani, look to end early as her late-game is pretty good once The Tuskraider has been played.
  • Until you’ve beaten The Hexcore Foundry, avoid picking draw bonuses as you could end up overdrawing easily in that fight. The AI board will usually be much wider in this encounter, so be careful about taking too much damage between their board pressure and Shrooms. Be wary of the Elusives and Sumpworks Map they will play.
  • Against Guard Bots, it’s important to be aggressive as they will be summoning 8/8 T-Hex‘es from turn 8 and on. All the previous turrets they summon only have 1 health so Overwhelm can be pretty effective here. Only one turret – a 6-cost Mk6: Floor-B-Gone – is Elusive also this keyword is also a good route to take.
  • Against Viktor, the key is to deny him the control of the board and remove the champion as soon as possible. AI usually trades pretty bad so being aggressive works well here.

I personally consider Lucian one of the easiest one to win with, as both him and Senna are capable of becoming really good carries.

Apart from the freezes in the Frejlord part of the run, there isn’t much that can happen to Lucian while in combat, so going all-in on him usually pays off great dividends.

Most aggressive power-ups are usually good to take here. Our starting deck isn’t built to go into long games and we want to invest either into units we can sacrifice to level Lucian fast, or into support to keep him alive. The best compromise usually is to buff Lucian and draft expendable units to go alongside him.

Almost the opposite of Lucian, MF is a champion that loves to be surrounded with carries to keep the attention away from her.

As such, the cards we want to focus on in the starting deck are the Prowling Cutthroat and the Island Navigator, they can net a ton of damage if we manage to give Scout to the Cutthroat or some beefy stats to the Navigator. ‘Domination’ passive which gives you Rally every turn is key.

As for the draft, our goal should be to build something close to a Scout deck, which can either go the direction of an unkillable Miss Fortune if we get Domination early or finding support spells for the two carries we have in the deck. Plunder cards are also very easy to activate.

Considered one of the hardest champions to win with, Lulu gives us a very difficult deck to work with. Her best card in the starting deck is the Young Witch, which can help dominate the trades and also deal some serious damage if enhanced early.

In a similar way as Miss Fortune, Lulu wants to be on the attacking side as much as possible and let her allies do the heavy lifting. She usually pairs well with a region that has access to combat tricks to protect her from being traded away.

What Ionia has going for it is the Elusive keyword. We will look for a way to either buff the Elusive minions or find a proper threat to give Elusive to with the Fae Guide.

Unless we had a great roll on the first few rounds allowing us to build a lot of pressure, picking some healing along the way can be a good thing, as we will likely end up with a not very reliable deck and will take quite some damage on the way.

Targon is a great region that has tons of tools to support various synergies. The problem is that theya are all mixed up in one weird-looking deck here. 

With a lot of value-oriented cards in the build, the real stars are the 2-drops. The Mountain Goat gives us Gems to make our trades efficient and to assist Aphelios’s weapon generation, and the Lunari Shadestalker is an Elusive unit, therefore worth buffing.

Aphelios alone can handle the late-game in most fights during the run – as such, investing in protecting and enabling him is usually a good route to take. Powers that help our mana – like refilling our gems or starting with more mana – are usually great to reach that comfort zone and be able to use Aphelios to his fullest potential.

Just like Lulu, Heimerdinger can be a pain to get through a perfect run. The champion pushes for a long, value-oriented gameplay that doesn’t really fit the way Lab of Legends works.

While it’s possible to draft to maximize Heimer’s potential with powers around spells and mana refills, the damage we have to sustain from one fight to the other adds up and that route can be risky without solid healing to fall back on. Most of the time, what worked best for me with Heimer was to draft for tempo and try to buff an Elusive minion while also investing into spell-oriented synergies.

That way, the deck still has a way to close out games. But if the game drags a bit long, then Heimer can come in and have enough support to be successful as he gives us a second wind with the Turrets he summons.

Utilizing a mix of the Vulnerable keyword and the landmark synergy, Taliyah decks can go different directions which all rely on tempo. Be careful when going the landmark way as you can encounter Aftershock in PnZ decks for the last part of the run.

The other problem Taliyah has is that the usual powers that you would like to pick up don’t synergize that well with the strategies she is pushing, and there are no powers that are related to the landmarks.

She is one of the most difficult heroes to complete the run with, as the new synergies from Shurima don’t really work well in the current set of possibilities the Lab offers as upgrades. This might be the champion where the first pick will be the most impactful, as it should give you the main game plan that Taliyah will likely end up only supporting.

The concept here is very close to the Lucian Azir deck you might see on the ladder. Azir deck is from the start filled with ways to dominate thanks to his Sand Soldiers. The deck offers a very clear path to follow and a lot of good targets are already in the deck.

We can either go towards heavy tempo, buffing our 1-drops to create an immense pressure from the start, or build some bigger units later to ensure we have pressure forever.

Azir has very similar gameplay to Miss Fortune, but starts with a better supporting cast. Just like MF, the passives that will help you get on board or attack as often as possible are premium here.

While the ladder isn’t as kind on him, Braum looks like he is having fun in the lab. The mode rewards you for investing a lot into one card, as we’ve covered already. Well, Braum might be just the best unit to invest into.

While his deck isn’t so good, the freezes and buffs we can benefit from at the start are enough for the first few rounds. After that, either find a second champion that can serve as the damage dealer, while Braum will be picking off the most dangerous threat each turn; or get some freezes and healing to be prepared for the long games Braum pushes for.

With a damage-oriented game plan, Riven can be very volatile. You have the potential to end extremely fast – especially in early rounds when opponents only have 10 health – but you can also feel helpless when the all-in damage approach is not enough.

Removal in the lab isn’t so common for the AI, and if you can defend Riven, leveling her up isn’t so difficult to do. Putting additional copies of Riven into your deck is also a good thing to do as her champion spell Riven’s Weapon Hilt can serve as a finisher the AI barely ever plays around.

There can be various viable passives and items that are viable for Riven – the basic ‘buff strategy’ works, but a spell synergy isn’t so bad either to discount the Blade Fragments. A 1-mana discount to spells is enough to achieve an incredible power spike and justify a Reforge build.

If you manage to find a second champion with a similar game plan, like Zed for example, or a Challenger which would take care of the trades and ensure some tempo advantage, you should have a solid chance at going through the 9 fights safely.

Hecarim has a great upside in that he can win games on its own, but he also has an issue – he costs 6 mana.

The direction we want to go here depends a lot on the first picks we will have – if the game offers us a better carry we should most likely take it. Otherwise, building for Hecarim is mainly about finding a way to at least keep up in the early game so we can dominate the mid-game.

The Ephemeral synergy is one of the most volatile and it forces us to take damage, which can be dangerous in the Lab. In order to go from one fight to another safely, and not lose it all on a bad draw, we have to find a way to protect our Nexus until Hecarim can come into play.

Everything related to mana cheats is obviously great in order to get to our comfort zone faster, and passives that add to the board will also help with controlling the flow of the early game. This might be the only tempo-oriented champion that we don’t want to buff too much as he comes so late in the curve. Instead, we can build a huge Shark Chariot, for example, which will net better results.

Closing Words

There we have our first Lab of Legends guide. Thanks to the various people who helped me with advice for the mode, there are different takes on how to tackle the lab and be effective – so I tried to include broad tips that you can make into your own.

As usual, feel free to drop by our Discord if you would have any questions or find me on Twitter if you need to contact me directly. Hope this was helpful in some way and best of luck in your future adventures in the Lab of Legends.

Good Game everyone,


Den has been in love with strategy games for as long as he can remember, starting with the Heroes of Might and Magic series as a kid. Card games came around the middle school - Yugioh and then Magic. Hearthstone has been his real breakthrough and he has been a coach, writer, and caster on the French scene for many years now. Although it took him a bit to get into Legends or Runeterra, his EU Seasonal Tournament win was the perfect start to get involved in the community. He now coaches aspiring pro players and writes various articles on the game. Find him on Twitter at @den_CCG!

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