Hammerkind

Hammerkind is John's kind abstratus, and the first kind abstratus to be seen in Homestuck.

Claw Hammer
John's first weapon. It was located on the floor in between his bed and the Magic Chest before he decided he would need it to hang up his Rolled-Up Poster. However, the Nails that were next to the hammer were also needed, leading to John dropping the Fake Arms to make room for them. It can be combined with the Nails to form...the hammer/nails. This can be used to hang up a poster.

Sledgehammer
It can be used to smash heavy duty objects and is probably the most powerful weakest hammer before alchemization, as John knocks himself out and breaks the sledgehammer when attempting to Aggrieve a Shale Imp, changing his Kind Abstratus to handlekind. The broken sledgehammer's handle is long enough to be a weapon in its own right, although it deals little damage, even against a Shale Imp. The broken hammer's head is capable of dealing some damage if ejected from a Sylladex. John's Kind Abstratus was restored to Hammerkind when he repaired the sledgehammer.

Pogo Hammer
Early in the game, the Pogo Hammer seemed to be a very powerful weapon, able to slay shale imps in a single blow. Rhythmically bouncing the hammer back and forth builds up its power, to be released in a burst of green light while attacking. This attack sends both the opponent's items and John flying off. John can also ricochet between two large enemies and fly through the air as a swirling green blur, due to his short stature being encompassed by the length of the hammer.

Wrinklefucker
The Wrinklefucker seems to be more controlled, and more powerful, than the Pogo Hammer, as John is able to bounce around killing Shale Imps with ease without springing too high into the air, as he did with the pogo hammer. John uses the Wrinklefucker to bounce himself up towards his First Gate. Due to the hissing noises it makes and the fact that it is part steam iron, it may deal heat damage as well.

The power of the hammer has its limits, as John tried unsuccessfully to attack a Copper Giclops and a Tar Basilisk with it. Previously, the Wrinklefucker defeated enemies with ease, but against stronger enemies it fails to make much of an impression.

It served as John's weapon of choice for a great deal of time, although he did dual-wield it with the Pogo Hammer. Ever since he alchemized Fear No Anvil, however, it has been tucked back into John's Strife Deck.

The steam irons that are mounted on the weapon seem to be two Shark Professional Series Intelligent Electronic Iron, GI490s.

Telescopic Sassacrusher
John does not have the strength required to lift it unaided, a problem he fixed by using the Remote Ghost Gauntlets.

It can easily dispose of Crude Ogres, and was used to get rid of at least two in the finale of Homestuck: Act 3.

It was stolen from John by a Copper Giclops, who absconded after being shot in the eye.

The Sassacrusher can be seen HS 4563 (later on), along with the Copper Giclops that stole it.

Fear No Anvil
A powerful hammer that Hephaestus used. Alternate Future Dave got the code from Hephaestus through "shenanigans" and gave it to John. Its name implies that it may have been Hephaestus' blacksmithing hammer. It appears to have some time-related abilities, including stunning enemies by stopping them in time. The extent of these abilities, however, is not yet clear. The clock that appears when the enemies are stunned portrays elements of the zodiac (e.g. a ram, a bull, a scorpion etc.) It may be reference to the trolls.

It costs 500,000 units each of Build Grist, Garnets, Diamond, and Gold, and one unit of Quartz, and is far too large to wield. John HS 3639 (alchemized) a smaller version, costing only 5,000 units each of Build Grist, Garnet, Diamond, and Gold and one Quartz. The inclusion of one piece of quartz is explained by the fact that some clocks use a small piece of quartz to keep time by subjecting the crystal to an electric current and measuring its vibrations.

Its name comes from the phrase 'Fear No Evil', implying that it is powerful enough to kill almost anything, as John would have nothing to fear of the enemies he'll encounter. Surely enough, it can dispatch a strong enemy like a thrice-prototyped lich with little trouble. However, when the fourth prototyping is completed, even a single imp becomes a threat, withstanding upwards of 50 (normal) hits before finally dying.

The name is an anagram for "LAVA INFERNO".

Its design appears to be themed after the Land of Heat and Clockwork; it consists of cogs, clock hands, and a head of Garnet.

The weapon itself is probably a reference to Hephaestus, from whom the weapon was stolen. In Greek myth, Hephaestus was the God of Blacksmithing, which further supports the theory of him being Dave's Denizen.

Warhammer Of Zillyhoo
In the Act 4 epilogue, a cyborg bunny appeared wielding a miniaturized version of the warhammer, along with three other weapons. John later recieves a monstrosified version through a series of shenanigans. By the time he runs out of sopor slime, Gamzee Makara appears to own a full-sized version of the Warhammer, filed in his jokerkind specibus. Later, he is seen holding it, letting Karkat behold its glory.

Pop-a-matic vrillyhoo hammer
This is an incredibly powerful hammer, able to kill the strongest enemy John has so far directly faced in combat (barring Bec Noir and possibly Typheus) in a single hit. This hammer bears an uncanny resemblance to Vriska's Doomsday device and the Warhammer of Zillyhoo. The handle may possibly originate from Ahab's Crosshairs, but then again, it may not. It is possible that HS 5725 (this sword) has something to do with the alchemization. The objects in the "popping" mechanism are potentionally the The flourite octet. In addition to this, it appears to don Vriska's "Scorpio" symbol and each end of the hammer seems to resemble one of her horns, concluding any suspicion of its connection to Vriska.

It probably was alchemized by combining the Flourite Octet and Warhammer of Zillyhoo, since John was possessing the latter and HS 5752 (got the code) for the former from Vriska herself. It is unknown if Vriska's ancestor's sword, Vriska's ancestor's diary, Ahab's Crosshairs, Vriska's Doomsday device and/or any other hammers possessed by John will be used in this alchemizing yet, and all of these (except Ahab's Crosshairs (in theory) and other hammers possessed by John) can not be accessed by John by the moment he woke up after his second impaling by Jack Noir. All of the resemblances to these items still would be a result of the Flourite Octet's connection to them.

This hammer was named by Andrew Hussie, via a summary of EOA5 on tumblr.

Unknown Problem Sleuth Hammer
The product of combining the claw hammer with John's Problem Sleuth Game, (HS 002967 (as seen here)) this hammer was long theorised to be the Warhammer of Zillyhoo. However, since the Warhammer of Zillyhoo has been shown to cost 1 Zillion of an unknown grist type, it is clearly something else.

Of course, its existence has so far proved to be completely without consequence, which is to say it will probably end up being the most important item in the game.