You heal based on the damage your hero does to an enemy.

It doesn't work when the enemy hits you.

A few other things to take into consider:

You don't heal a lot if the hero wearing the life steal gear isn't a damage dealer.

Ideally, you want the hero wearing the Life steal gear to do enough damage so that the heal can fully top you up.

Lifesteal in my op,is worthless with out warmaster masteries. Your champs wont function right with lifesteal untill you use warmaster )Hope that helps    

Player J said:

You heal based on the damage your hero does to an enemy.

It doesn't work when the enemy hits you.

A few other things to take into consider:

You don't heal a lot if the hero wearing the life steal gear isn't a damage dealer.

Ideally, you want the hero wearing the Life steal gear to do enough damage so that the heal can fully top you up.

Thanks, PJ, for yours and other comments made. You answered my question, but it seems just a matter of degree as to how much healing you get.  I generally shy away from too many 4 item sets cuz you miss out on multiple 15% bonuses that the 2 item sets give. But these Lifesteal items seem easy to acquire and offer decent stats for my purposes.

One thing seems certain, that whatever champ you apply the Lifesteal on, the healing will increase as you make the champ more powerful. I am using a 2* champ Head Taker for illustrative purposes.

Lifesteal is great for boss fights of all sorts, because with the proper Mastery, your champion will instant heal on a hit.

WatchdogCZ said:

Lifesteal is great for boss fights of all sorts, because with the proper Mastery, your champion will instant heal on a hit.

I have my Siphi in Lifesteal for the Clan Boss. Her A1 usually heals her fully, if the big damage occurs.

There is the key with the proper Mastery TY :)

killerclone187 said:

WatchdogCZ said:

Lifesteal is great for boss fights of all sorts, because with the proper Mastery, your champion will instant heal on a hit.

I have my Siphi in Lifesteal for the Clan Boss. Her A1 usually heals her fully, if the big damage occurs.

There is the key with the proper Mastery TY :)

I am saving up for my first batch of 800 gems, almost there, so I can buy my first cluster of all the masteries on a champ.  Up to now the most I have gone is the first 2 rows in the Minotaur, so where would the Warmaster be?