Bridge Constructor
58 Achievements
99,000 XP
Offside
Completed all optional levels.
1,500 XP
4.31%
How to unlock the Offside achievement in Bridge Constructor - Definitive Guide
The bridges that are optional are:
Westlands
• Bridge 4
• Bridge 7
Central Mainland
• Bridge 4
• Bridge 7
The Ridge
• Bridge 2
• Bridge 6
Eastern Mainland
• Bridge 4
• Bridge 7
Tamassee
• Bridge 2
• Bridge 6
You will most likely get this simply by going through each of the 8 bridges for the other achievements anyway.
This trophy is tied to the Camatuga map; any levels from the SlopeMania - Tiltin Islands map do not count. Camatuga has 5 islands. Each island has 6 required bridges plus 2 optional bridges. Therefore this trophy requires you to complete all 10 (5 islands x 2 optional bridges) optional bridges in Camatuga. The trophy will unlock during the success screen of the 10th optional bridge that you complete. They do not have to be completed in order (but do require main bridges to be unlocked in order to access these optional levels).
This will unlock on your way to "Truck insignia 'Tamassee'" as the optional bridges are required for 100% of each island. For reference, the optional bridges are the bridges that aren't connected by the 'roads' on the map select screen and aren't needed to advance to the next level but that still use the same rules as the other maps.