As of March 2018 Mobile Legends official website doesn’t have enough documentation about items. The only available item documentation in that website is the recommended items for each hero. There is no descriptions about the items themselves, not even item names.
The only official documentation about items is in the game itself. Even then, you need to play the game in order to see the full documentation. In the lobby there is no documentation about item recipes nor tier 1 and 2 items.
This is another attempt to document the items. The differences with the other item documentation sites are: the entire item descriptions are in one page, nothing is folded / hidden so I can search with CTRL+F, there are links to quickly jump between related items, and this is a way for me to practice generating a page with JSON in Jekyll :)
Unique Passive Swift: Every 1% of critical chance will add 1% attack speed.
Unique Passive Endless Strike: Basic attack adds a stack of Endless Strike. After accumulating 2 stacks of Endless Strike, the effect of the next basic attack is triggered 3 times.
Unique Passive Typhoon: Every 3.5s basic attacks hit 3 enemy units and deal 100 point of magic damage. This effect's cooldown drops as your critical chance rises, while damage rises as attack speed rises.
Unique Passive Activate: Each time Typhoon is cast, hero's movement speed increases by 5% for a short time.
Unique Passive Soul Steal: Eliminating hero grants 5 Soul Stacks. Assisting grants 3 stacks. Stack of 15 converts into 25 points of magic power. Lose all stacks on death (already converted stacks are unaffected). Max 50 magic power.
Unique Passive Soul Steal: Eliminating hero grants 5 Soul Stacks. Assisting grants 3 stacks. Stack of 15 converts into 25 points of magic power. Lose all stacks on death (already converted stacks are unaffected). Max 100 magic power.
Unique Passive Exterminate: After a skill hits a target, magic power will immediately increase 15%. The next skill damage will terminate this effect. Lasts 3s. Cooldown 10s.
Unique Passive Scorch: Burns the target for 3s when the skills hit, deaing 2% / 3% / 4% of the target's current HP as magic damage (10 damage minimum).
Unique Passive Calamity: After using a skill, the next basic attack deals extra true damage equal to 120% magic power. Cooldown 1.5s. Briefly raises movement speed by 10%.
Unique Passive Bravery: Increases 10% attack power and defense for nearby allies.
Unique Passive Heavy Armor: Nearby soldiers can take more turret damage.
Unique Active Encourage: Raise the movement speed of hero and nearby allies by 30%. Raises physical attack and magic power by 20%. Lasts 3s. Cooldown 40s.
Unique Passive Thunderbolt: After a hero uses a skill, the next basic attack deals bonus damage that equals 2% of the hero's total HP. The enemy target and surrounding units are slowed for 1.5s. Cooldown 1.5s.
Unique Passive Recovery: Regenerates 1.5% of hero's total HP. Eliminating enemy hero raises regeneration rate by 0.4% while assist only raises the rate by 0.2% (includes elimination and assist prior to purchase) up to 3.5%. This effect deactivates when the hero takes damage and reactivates 5s after the last time taking damage.
Unique Passive Greed: Get an extra 30% exp when jungling. Regain 4% of max health and 10% of mana after monster kill.
Unique passive Gorge: Increases damage by 0.5% on killing a jungle monster, stacking up to 2 times.
Unique Passive: Makes the battle spell retribution applicable to heroes: Reduces target's movement speed 70% (The effect will decay within 3s) and reduces target's Magic Resistance. Buying other advanced jungle gear will disable this effect.
Unique Passive Greed: Get an extra 30% exp when jungling. Regain 4% of max health and 10% of mana after monster kill.
Unique passive Gorge: Slaying jungle monster increases hero's armor and magic resist by 3 up to 10 times.
Unique Passive: Makes the battle spell retribution applicable to heroes: Reduces target's movement speed by 70% (The effect will decay within 3s) and within a short period of time receive a shield that scales off max health. Buying other advance jungle gear will disable this effect.
Unique Passive Greed: Get an extra 30% exp when jungling. Regain 4% of max health and 10% of mana after monster kill.
Unique passive Gorge: Slaying Jungle monster increases your physical attack by 4. Stacks up to 10 times.
Unique Passive: Makes the battle spell retribution applicable to heroes: Reduces target's movement speed by 70% (The effect will decay within 3s) and dealing small amount of true damage. Buying other advance jungle gear will disable this effect.
Unique Passive Greed: Get an extra 30% exp when jungling. Regain 4% of max health and 10% of mana after monster kill.
Unique passive Gorge: Increases damage by 0.5% on killing a jungle monster, stacking up to 2 times.
Unique Passive: Makes the battle spell retribution applicable to heroes: Reduces target's movement speed 70% (decays over 3s) and reduces target's Magic Resistance. Buying other advanced jungle gear will disable this effect.
Unique Passive Greed: Get an extra 30% exp when jungling. Regain 4% of max health and 10% of mana after monster kill.
Unique passive Gorge: Slaying jungle monster increases hero's armor and magic resist by 3 up to 10 times.
Unique Passive: Makes the battle spell retribution applicable to heroes: Reduces target's movement speed 70% (decays over 3s) and for short period of time grants a shield based on max HP. Buying other advance jungle gear will disable this effect.
Unique Passive Greed: Get an extra 30% exp when jungling. Regain 4% of max health and 10% of mana after monster kill.
Unique passive Gorge: Slaying Jungle monster increases your physical attack by 4. Stacks up to 10 times.
Unique Passive: Makes the battle spell retribution applicable to heroes: Reduces target's movement speed 70% (decays over 3s) and dealing a small amount of true damage to the target within 3s. Buying other advance jungle gear will disable this effect.