Siege Crossbow
Craft guide

Deterministic Gem-Level Ballista Crossbow

Base: Magic Siege Crossbow with increased physical damage AND a plus to projectile skills roll (mid budget, a few divines)

Based on Endgame Crossbow Crafting Guide

Buy the double-rolled magic base
Filter trade for magic, increased physical damage plus level of projectile skills - buying the gem levels on the base is what makes the rest deterministic
Slam a Greater Essence of Abrasion
1× Greater Essence of Abrasion
Rare with guaranteed flat physical damage on top of the increased physical roll
Desecrate with both omens active
1× Omen of Sinistral Necromancy
1× Omen of the Sovereign
1× Preserved Jawbone
Prefix desecration with a guaranteed extra ballista totem waiting at the reveal
Fill every open mod
2× Greater Exalted Orb
All six mods must be filled before the next step - an exalt should say the item has no space for mods; Omen of Greater Exaltation on one slam saves an orb
Socket Astrid's Creativity
1× Artificer's Orb
1× Astrid's Creativity
The rune allows a second crafted modifier alongside the essence mod
Slam a Perfect Essence of Battle
1× Perfect Essence of Battle
With all mods full it replaces a suffix and guarantees plus three gem levels
Reveal at the Well of Souls
The Sovereign omen makes the plus one ballista totem guaranteed
Quality, runes and infusion
20× Blacksmith's Whetstone
2× Greater Iron Rune
1× Masterwork Rune
Masterwork Rune upgrades a Greater Iron Rune to Perfect; you can pull Astrid's Creativity afterwards - the crafted mod stays
Vaal Blacksmith's Infuser (optional)
1× Vaal Blacksmith's Infuser
Each infusion adds quality past 20 but can corrupt the weapon - mods are untouched, it just stops further changes
✓ 600-plus phys DPS, extra totem and gem levels
Materials
1× Greater Essence of Abrasion
1× Omen of Sinistral Necromancy
1× Omen of the Sovereign
1× Preserved Jawbone
2× Greater Exalted Orb
1× Artificer's Orb
1× Astrid's Creativity
1× Perfect Essence of Battle
20× Blacksmith's Whetstone
2× Greater Iron Rune
1× Masterwork Rune
1× Vaal Blacksmith's Infuser
Cost per pass≈0.0 ex
Expected cost≈0.0 ex
Total excludes 12 unpriced materials.