The second upgrade to the Weight Trap category, it has an upgrade cost of 5000 gold.
Going from the Metal Ball Trap (Rank B) to The Fire Bomb Trap (Rank A) has the following effects :
- increases the MP cost from 300 MP to 500 MP
- Success % increases from 5% to 7%
- Power increases from 40 to 60
- Duration is not affected by the rank upgrade.