Board Thread:General Discussion/@comment-1328622-20150217031918/@comment-17760674-20150218201101

Efficiency = target stat (attack, defense, total) divided by spirit

You know how you'd rather use a card with 6000 attack and 15 spirit than a card with 5000 attack and 16 spirit (assuming that their skills and skill levels are the same)? Yeah, that's what efficiency is, but put into number format xD