In Lords Mobile Wall Strength III research increases the max HP of your walls. It is found in the defense tree.
There are 10 levels in total and once maxed you will have increased your wall HP by 275,000. You need to have researched all the tier 3 traps before you can unlock this ability.
The table below has the resource cost and time to upgrade each level. It also shows the might and rewards granted. You can find out your own research time by using our research calculator.
Wall Strength III Research Requirements
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