im thinking of going into a fat pack for Theros or BotG? which should i choose?
Botg! And buy on eBay. Way cheaper!
Tough call. Here's how I see it though.
Both have decent value in them
+1 both
If you don't have much or any of either set, Theros is a much larger set and you will open a much wider variety of commons and uncommons
+1 Theros
If you want to draft or play limited with the packs, Theros was designed to play by itself, and Born of the Gods was not. Limited with all Born packs would be mechanically unbalanced.
+1 Theros
If you're looking for a specific card or cards, you're more likely to open it in a smaller set (Born) than one with more variety (Theros)
+1 Born
If you've played as much Theros as I have, you might just be sick of it and/or already have a playset of all non-rares. A fat pack for 9 rare cards and 1 or 2 foils? No fun!
+1 Born
Now, look through those points and only count the +1s on the points that relate to you. Should put a perspective on it!