Now is the perfect time to farm BB fodder why?

Low energy cost (mostly 3 energy)

DOUBLE HONOUR PTS ( 80 per friend)

METAL CRYSTALS IN HONOUR SUMMON

in the long run, you'll be getting more honour pts per energy and some BB fodder on the side

XP BB fodder = hello SBB!

Taken from [http://www.reddit.com/r/bravefrontier/comments/266oih/general_brave_burst_leveling_guide/] Locations for Attack feeders :

Mistral -- Adventurer's Prairie -- Start of Adventure (Burny and Friends)
Mistral -- Cave of Flames -- Wielder of Fire (All units except for the Fire Nymph)
Morgan -- Kagan Desert -- Burning Desert / Bandit of the Desert (All units except for Fire Spirit)

Locations for Healing feeders :

Morgan -- Nocturnal Forest -- Thief of the Forest (Fairies and Claris)
Morgan -- Nocturnal Forest -- Earth Shattering Spear (If you need Guardian Eyes) (Fairies and Claris)

Locations for Support feeders :

Mistral -- Forest of the Beast -- Puppeteers of the Forest (Mandragoras)
Mistral -- Magutagal Wetlands -- Commander of Thunder (Harpy)
Morgan -- Nocturnal Forest -- Thief of the Forst (Mandragoras)
St. Lamia -- Mt. Wistorea -- Tarnished Peaks (Aero/Harpy and Sylphs)

Credits to /u/alexisevan