The first upgrade to the Cage Trap category, it has an upgrade cost of 4000 gold.
Going from the Copper Cage (Rank C) to The Jail Cell ( Rank B) has the following effects :
- Increases the MP cost from 250 MP to 450 MP
- Success % increases from 2% to 3%
- Hold per second increases from 6 seconds to 12 seconds
- Duration is not affected by the rank upgrade.