DotA Myths and True Facts

1 : Myth:
Pressing F1 or ctrl + 1234567890 which already binded to your hero all together will make you regen faster than normal in your fountain.

Fact:

False. The regeneration rate is still the same, only the number refreshes faster.
2 :  Myth:
Buying Vlads will get your illusions a lifesteal.

Fact:

False. Illusion didn't get the lifesteal effect from Vampiric Aura or cleave from Battlefury. However, illusion can still get Feedback orb from Diffusal Blade (only melee) and Radiance aura.
3 : Myth:
Using Battlefury, the Omnislash are cleaved.
Fact:
False. Only the additional slash will be cleaved. The true slash will remain intact without cleave.
4 : Myth:
Quelling Blade makes last hitting easier.
Fact:
Half true. While it can help you increase the damage for last hitting creeps, on some heroes like Leviathan, Nerubian Weaver and Juggernaut, their attack animation is changed and thus make it harder to last hit.
5 : Myth:
Stacking Vanguards increases your block damage.
Fact:
False. Stacking Vanguards increases the block chance, not the block number.

With 2 Vanguards you will still block 40/20 (melee/range) dmg, but at a higher percentage (70% for 1, 91% for 2).
6 : Myth: 
Dropping items that give int but no mana reg while at fountain will make you regen faster.

Fact: 

True. Fountain mana regeneration is based on max mana % + 7 mana/second. So, dropping an energy booster, int threads, etc, will make you regenerate your mana faster at fountain.