Here is a simple word game that might prove some fun.
What is the longest grammatically correct sentence you can come up with where all the words begin with the same sound (such as mmm in mountain or k in kitchen). Obviously in some sounds you can use different letters to make the same sound, such as ess (service, cerulean).
The only words starting with a different letter that you are allowed in your sentence are the following: Prepositions, Prounouns and the various forms of the verb "to be" (past, present, future, pluperfect, etc).
The sentence can be quite silly (this may be part of the fun), but must be grammatically correct.
Here is an example:
Military Martians muster in Madrid managing to mask themselves as molecular machines.
The President promised political parity while promoting a pedantic policy on polar positions: "Pungent Politicians: Profiling Preferences of the Paradoxical and Pedantic."
Rambling rioters rumble in remorse, remitting recalcitrantly written reports of refuse ranging the roads of a remote Russsian region riddled with rings of ransacking ruffians of a rancorous retinue.
Sorry to be the bearer of bad news Josh, but given that Buffalo and buffalo can only be nouns, or possibly as an adjective (as in buffalo wings) your phrase cannot be considered to be a sentence. You do get points for being faithful to the onomatopoeia rule.
"Surely, Sir Sam," simple Simon said soundly, " since Sunday, sister Suzi sings serious songs so sweetly, sweet songs so seriously, and silly songs so smartly."
Buffalo-based buffalo, Buffie, became befuddled by being buffaloed by brother Buffalo buffalo, Brandon, because battles between buffaloing brother Buffalo buffalo befouls the best buddies that Buffalo buffalo became by being branded bogus buffalo by big bison beyond Butte.