Lukas

Complete physical wall Lukas. This build can single-handedly take down almost every physical hero 1v1 over a few turns. Ignis proc means almost certain death, Renewal to keep Lukas healthy.

Lukas is OP and catches a lot of flier emblem teams off guard (due to the fact flier emblem teams consist of mostly if not all physical units). Lukas’s monsterous Defense is amazing and his attack is good too.

Keep Killer Lance unless you got a second Nephenee becuase you can’t get + weapons at 5* for some reason.

Since he has the defense, you can keep fragile mages like Delthea from impending doom. Swap can tank and then kill them next turn.

Bonfire is used becuase it’s a 2 turn special with Killer Lance. Ignis can be used too, but Ignis is a 3 turn special with Killer Lance and Lucas is slow AF so you might want a faster special.

Armored Blow is literally to make everyone else be like -_- while you’re like “no damage b*tc**s.” No seriously he can tank a whole lot of units efficiently. Ike with hone Atk, +Atk boon, can only do only 8 damage. (2 with armored Blow). Hawkeye can do 22 damage but it’ll be shortened to 16 with Armored Blow. Cherche with Brave Axe can deal 34 damage which is quite a lot. With armored Blow she only deals 22. Long story short, it is much better to use this if you plan to go offensive. You can of course use Death Blow but I find it harder to find as the days progress.

Brash Assult is chosen, but if you don’t like using it then you can definitely use a breaker skill like Lancebreaker or Blue tome Breaker. It is very flexible. Just don’t use Obstruct. Brash assult means that Lukas will double when he’s at lower than 50% hp. This is extremely useful if you find him in a pickle.

Threaten Atk is so that he can last just a little bit longer. -5 Atk to foes in two spaces means that he has the chance to negate 10 damage. If you read the paragraphs before, this means Ike will do absolutely no damage. Hawkeye will deal very little while Cherche will deal 10. Yes 10 damage only with brave Axe. 34 damage to 10 damage. This will ensure Lukas survives Axe units.

Lukas is a defensive wall, probably one of the best in the game and can be very good. The way i have him built is to prolong the fights as long as there are no mage units around because any mage will destroy him very easily.

Costing some atk, fortress def 3 grants him 5 more def and with a def boon he can get to 46 def and with the help of other allies he can get to over 50 def which is better than or equal to the armor units but since he is infantry he can move much easier.

Renewal 3 helps him retain his bulk in consecutive fights and instead of swap you could give him reciprocal aid or ardent sacrifice to make him a healer since he has great HP. Threaten Atk simply helps his bulk but if more damage is needed threaten def or def ploy can be used.

He comes with a killer lance which helps his cooldown rate for his special and allows him to equip skills that have higher charges like ignis which really boosts his damage. You can give him a stronger weapon if you have the quicken pulse seal but his atk stat is high enough for him to deal enough damage.

I use swap instead of reposition, to help position him to the front lines but the latter could work as well, pairing him with a dancer can help him bait enemies as well.

All in all Lukas is a great wall, with enough power to back it up.

Build intended to allow Lukas to effectively combat all physical attackers. Deft Harpoon+ is a very good weapon for this, as it has base 14 MT, just short of Silver Lance+, as well as the innate Fury 1 effect at 100% HP. This is where Renewal helps him out; as long as he doesn't meet any dragonstone or magic users, it won't be difficult to maintain 100% HP for the Deft Harpoon's effects while Lukas plays a role of baiting, almost never initiating unless he's taken damage. I chose Reposition for my support skill, but this is entirely up to the player. Ignis allows Lukas to add over 30 damage to his base attack, or just over 20 if using Bonfire. Fortress Def is intended to help Lukas tank more hits; the Deft Harpoon compensates for most of the loss in Atk and boosts Fortress Def's effects. At 100% HP, the buffs Lukas receives in combat bring his statline to 48 Atk (49 with Attack +1 seal which is recommended), 24 Spd, 48 Def, and 15 Res. As you can see, his Atk and def are all that really stand out, and that's all you need to focus on. He can still ORKO many physical units, and their doubling him is almost always useless as it does 0 damage more often than not. Their doubling also adds charge to Ignis. Should you come to find a Brave weapon user, charging special will become even easier. The rare occasion he will have to initiate combat is against shuriken and bow users. Preferred Sacred Seal is Attack +1, as Quickened Pulse does little considering Lukas is meant to ensure a victory, not to end it quickly.

This is a combination of both an offensive and defensive build, in case you require a wall, but you still need some destructive power.

Guard's usage is explained in a reddit post (https://www.reddit.com/r/FireEmblemHeroes/comments/6ppu2m/best_boy_lukas_makes_a_case_for_guard/), where he will not be destroyed by specials such as Moonbow, Luna, Glacies, Ignis, and Black Luna (when it eventually comes out). Quick Riposte is also fine here, if Guard is unavailable.

Bonfire can be replaced with Ignis; I just tend to like Bonfire more due to its shorter cooldown, especially since Guard is chosen instead of QR here.

C skill is, as usual, flexible.

Ideal IVs would be +Atk/-Spd (since his defense is already high enough, and you're going to be doubled by almost everyone anyways).