This is going to be a very high tier damage item towards AD (Attack Damage) casters and fill a void with an flat armour pen item being removed.
The Giant's Hammer: Recipe: B.F. Sword (1550g) + The Brutalizer (1337g) + 713g = 3600g
Statistics: +80 Attack Damage +20% Cooldown Reduction +UNIQUE Passive: 15 Armor Penetration plus an additional +1 Armor Penetration per 10 bonus Armor the target has. +UNIQUE Passive: When below 40% health, gain +40 Attack Damage.
Serf Master1 votesJust another armor pen item is good, i dont ask for more.
Stacona1 votesWhat about a high tier Brutalizer that scales with Last Whisper really well? Because this is basically an upgraded Brutalizer
Stiv12341 votesI wouldn't want to see a Riven run around with this thing...
Also, the passive is basically 10% bonus armor penetration.
Stacona1 votesbasically- it is only effective against tanks outside the brutalizer half of it - it scales better with last whisper though since flat pen applies after % pen the item is to be good with ad casters, but i tried not to have it too dominating against squishies the item is mainly a late game brutalizer- it will help champions like Graves make a comeback
something I always say is one champion should not stop the game from making more item diversity, when that one champion should already be receiving hefty nerfs now
Dunkrius2g1 votes
"heavy breathing"
You either remove some passives or you gotta make that 4.5k gold.
The only items that can give you the most raw damage is 
or a fully stacked
. On top of that, you are giving Flat armor pen. It is good against squishys but like I said. You either remove some passives to make it be worth 3.6k or you leave passives and actually make it cost 4.5k
Stacona1 votesYou have the flat armour pen from brutalizer
Dunkrius2g1 votesYes. Problem arises is that you get too much for too little gold. 3.6k is a lot but still for the passives, it needs a hefty price. To make it better or more "acceptable", you will have to remove the last Unique passive. Making it 15% CDR and making the price for 3600 will be fine.
Other than that meaning if you want all these stats, then you will have to change its price to 4k or more.
Stacona1 votes10% CDR is 300 gold the additional armour pen is only relevant against tanks who build armour and even then it is powerful with a last whisper and not on its own in this area so this is 5900 gold
when you are below 40% health you get 40 Attack Damage , directly this is 1200 gold in AD - so with the second passive and almost dead making it a high risk high reward passive you are 800 gold efficient or 400 gold inefficient while the second passive is not in effect--- all high tier items need to be directly gold efficient or gold efficient through other items (like how deathcap and infinity edge work) this item falls under a hybrid of both areas it is not exactly efficient on its own unless a requirement is met, but also becomes gold efficient through armour pen items like last whisper
tl:dr : i know math