Yes, I know it's early to revise Ravnica (like, 7 yeaes early), but I liked the set, so I created a cycle around its guils. I will post one card of the cycle per day, starting with this one:
Boros Guildhall

Enchantment- Guildhall
Creatures you control have haste, first strike and vigilance.
Creatures with multiple instances of first strike, haste or vigilance gain +1/+1.
My problems with every card of the cycle are:
-the names are placeholders. I'd like to have something that resembles the guild's philosophy, but could still be a guildhall (difficult for Rakdos and Gruul)
- I have no idea about the power level; I want them to be very good, but not broken. And they should be quite equally good
-Some have strange wordings (this one, for example) that might have to be fixed
and finally
- Are the abilities balanced (meaning equally red/white, in this case)? Does it matter if some of the cards use guild keywords (like dredge) and some do not?
Szadek's Guile

Enchantment- [Subtype]
At the beginning of your upkeep, look at the top 2 cards of target player's library. You may put any number of those into its owners graveyard.