There's an opportunity in Blood & Glory: Legend to earn free Rubies/Credits, though some options and here's a small sampling of ways to grab free gems.
Become a fan of Blood & Glory Legend on Facebook: 2 Rubies
Sign up for Netflix: 340 Rubies
Yahoo! Fantasy Football (Join a league): 20 Rubies
Subscribe to Disney Movie Club: 408 Rubies
Enemies also have special attacks, designated by color. Orange means it cannot be blocked, while white means it cannot be dodged.
You can revive after losing a fight and it costs two rubies.
There are three Super Combos in the game. Check the Options menu to find out how to execute them.
Glu Mobile will let you know, before a battle, if an enemy has superior gear. This way you can upgrade before battling.
Upgrade your equipment whenever you can. Green means that particular item is stronger than what's currently equipped, while red signals that it's weaker.
Keep an eye out for the caravan for a free item.
In-game achievements let you pick up valuable rewards, so always keep them in mind.