There are a number of contraptions that can be constructed using the Engineering Skill. To create these contraptions, craft them from the Crafting Table menu. Crafting contraptions gives both Crafting and Engineering XP. After the contraption is crafted, it can be used at any time by clicking on it in your inventory.
Barricades can be crafted from Planks (created from Logs at the Sawmill outside the Capital and the Abandoned Village). When used from the Inventory, the player can place a Barricade where they stand, that blocks movement. Only 10 barricades can be set up per player. Barricades can be destroyed by other players, either by attacking it or lighting it on fire (requires 40 crafting). Players can destroy their own barricades instantly at any time. Barricades give Engineering XP on construction and are part of the Engineering skill.
Players can use Gate Teleport Scrolls to create portals to the Capital City or New Mortis. Activating a scroll creates a portal that teleports players to the city specified by the scroll. Only one portal can exist per player at a time and they expire after 15 minutes. Portals can be destroyed by anyone. Central Portals in city centers allow players to teleport back to their placed portal, refreshing its timer. Be aware, using teleport scrolls without being adept in magic could lead to being dealt significant damage - the higher your magic level, the less likely it is for this to happen. Portals give Engineering XP on construction and are part of the Engineering skill.
Traps are player-constructable objects that allow players to trap either NPCs or players that run over them. Traps can be constructed with the Engineering skill.
Behavior
Traps work like barricades, but when set up, do not have collisions. Traps you set up are not visible to other players (Trap Reveal spells, Torch revealing coming soon).
Effectiveness
Each trap rolls a chance to be effective when triggered. If a trap is not effective, it will still trigger / be used up, but the player will not get negative effects (stun/movement push/poison, etc.).