I need a rioter or someone who know his stuff to explain some masteries how they work

Runic Armor: +1.6%/3.2%/4.8%/6.4%/8% bonus to all shields and healing on you (includes lifesteal and regeneration) About This mastery does it work with the life steal that provide the machete vs monster? and if yes it goes at 16%? (The new machete would give 8% life steal vs monsters)

Bond of Stone: +4% Damage Reduction. While near an ally this bonus is doubled and 8% of the damage they would take from champions is dealt to you instead (cannot reduce you below 15% Health). About this mastery how it work? i mean what if you are with 4 allies which ally would "protect" and you would recieve 8% of the damage they take? or does this work with all 4 meaning that you may "tank" 32% damage of the damage that the 4 allies took? and which target ressistances would take in factor? yours? i mean lets say someone hit an ADC with 100 damage the adc would have lets say 50 armor the damage that you would tank is the damage that this target you take or you will tank it as it hit you and lets say you have 200 armor the 8% that you will "tank" would hit as it hit you and not the target with the 50 armor? this mastery is kinda weird and it need an explanation!

Feast: Killing a unit restores 20 Health (20 second cooldown) (This mastery really need a buff...)