This is all the information about the game (What you need to play it....all those thing)
POWERED BY THE E.V.I.L. ENGINE
60 frames per second!
Sub-30ms control responsiveness
1.3 million polygons in the game map
WORKS ON THE FOLLOWING DEVICES
iPad Air, iPad mini with Retina Display, iPad with Retina Display, iPad 2 (30+fps)
Needs iOS 6.1 or later
iPhone 5s, iPhone 6, iPhone 6 Plus
Needs iOS 8.0 or later
NO COMPUTER !
You can dowload the game in the Store.
About the objectives :
The rules are simple. Two teams battle to destroy a giant crystal in their opponent’s base. Think of it like capture the flag, but with crystals.
Here is the basics about Vainglory
Also Some gameplay by IGN
As you can see , only one lane and a jungle. Also no fog.