In Lords Mobile Survival Tactics I research increases your heroes max HP when attacking monsters. It is found in the monster hunter tree.
There are 10 levels in total and once maxed you will have increased your heroes health by 21.25% (only when attacking monsters). You need to have unlocked aggressive hunter I in order to research 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.
Survival Tactics I Research Requirements
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