The Workshop is unable to function when being upgraded; since a player can only have one Workshop at a time, this disables Siege Machine production while the Workshop is being upgraded.
You can boost Siege Machine production using Gems; this costs 30 Gems and speeds up Siege Machine construction by a factor of four.
The Workshop, like the Spell Factory, holds the items built within (in this case, the Workshop holds constructed Siege Machines). However, even though multiple can be kept in the Workshop at once, only one Siege Machine can be used per battle.
You do not lose constructed Siege Machines if the Workshop is destroyed during battle; the Workshop's destruction also will not hinder Siege Machine construction in any way.
Siege Machines can be donated to players with Clan Castle level 6 or higher.
When initially constructed, the Workshop has several features; one of which is a red-roofed hut with similar shape to that of a Builder's Hut. On top of this hut is a crane with a wooden jib, a metal hook, and a stone counterweight. Beside the hut is a crate with an unfolded blueprint of a battering ram, a likely reference to the Workshop's ability to build Wall Wreckers. Behind the hut, there is a small pile of wood. A single white dotted rectangle is present in the surrounding grass at one corner, indicating its ability to hold one Siege Machine.
When upgraded to level 2, the pile of wood behind the hut is built into a wooden platform, with two red balloons attached to the corner of this platform. The battering ram blueprint is now presumably rolled up and placed to the side; in its place is a blueprint of an airship, signifying the Workshop's ability to build Battle Blimps. A second white dotted rectangle appears in the grass next to the first one, indicating the Workshop's ability to hold two Siege Machines.
When upgraded to level 3, a large boulder appears in place of the wooden platform. A third red balloon is added, and the crane's jib is reinforced with metal. The blueprint of the airship is again presumably rolled up and placed to the side, with a new blueprint of a hot air balloon visible, signifying the Workshop's ability to build Stone Slammers. A third white outline appears in the grass, indicating the Workshop's ability to hold three Siege Machines.
Tapping this icon displays information about the Workshop, such as Level, Siege Machine Capacity and Hitpoints.
Tapping this icon begins upgrading the Workshop to the next level, if you have enough resources and a free Builder. When the Workshop is at maximum level, this icon is not shown.
Tapping this icon instantly upgrades the Workshop to the next level, at the cost of one Hammer of Building if you have one. When the Workshop is at maximum level, this icon is not shown.
Tapping this icon, which is displayed only while an upgrade is in progress, instantly finishes that upgrade at the cost of the displayed number of Gems.
Tapping this icon, which is displayed only while an upgrade is in progress, instantly finishes that upgrade at the cost of one Book of Building. This icon is only shown if you have at least one Book of Building.
Tapping this icon, which is displayed only while an upgrade is in progress, boosts all your Builders for 1 hour by a factor of ten, at the cost of one Builder Potion. This icon is only shown if you have at least one Builder Potion.
Tapping this icon, which is displayed only while an upgrade is in progress, cancels the current upgrade and refunds half of the upgrade cost.
Tapping this icon boosts your siege machine training for 1 hour, reducing the time required to train Siege Machines by a factor of four for the duration of the boost.
Tapping this icon boosts your siege machine training, spell brewing and hero regeneration for 1 hour, reducing the time by a factor of four for the duration of the boost, at the cost of one Training Potion. This icon is only shown if you have at least one Training Potion.
The Workshop is one of only two buildings in the game being 5x5 tiles, the other being the Army Camp.
Its appearance could be inspired by the Builder's Workshop, the Arena 6 in Clash Royale. This Arena has a "siege" theme, as it unlocks the Clash Royale counterparts of the Mortar and the X-Bow, which can directly attack the opponent's towers.
The Workshop's red balloons resemble those of the Skeleton Barrel, a temporary troop from Clash Royale, also unlocked at this Arena. The Siege Machines' mechanics could be inspired by the Skeleton Barrel - reaching a building and release troops inside.