An average agility hero physical resistance at late game 65%.
An average agility hero magical resistance at late game 33%.

At level 25 with BKB and Guinsoo:
Physical dmg 237 82.95
Magical dmg 0 0 Total: 82.95 dmg/hit 3.253 hit/s 269.83 dmg/s

With MKB
Physical dmg 289 101.15
Magical dmg 75 50.25 Total: 151.4 dmg/hit 3.318 hit/s 502.29 dmg/s

With Buriza
Physical dmg 446.88 156.41
Magical dmg 0 0 Total: 156.41 dmg/hit 3.253 hit/s 508.79 dmg/s

With Moonshard: +26.94% attack speed compared to without Moonshard
Physical dmg 237 82.95
Magical dmg 0 0 Total: 82.95 dmg/hit 4.129 hit/s 342.53 dmg/s

So it is better to buy MKB for cost effectiveness and True Strike.


After buying MKB, the next item:

With Buriza
Physical dmg 518.38 181.43
Magical dmg 75 50.25 Total: 231.68 dmg/hit 3.318 hit/s 768.63 dmg/s

With Moonshard: +26.42% attack speed compared to without Moonshard
Physical dmg 289 101.15
Magical dmg 75 50.25 Total: 151.4 dmg/hit 4.194 hit/s 634.99 dmg/s

So the next item should be Buriza.