7:30 AM

[Bananadon]

Ring, Ring.
The alarm clock's mechanism reverberates;
An army of sound, Intent on attacking
My ear drum's morning defences, lacking.
The troops quickly rally,
As the tumult, heard early,
Echoes through my ear.

Clink, clink.
Ear-drum warriors surge together,
Ready to embrace the banshee's shriek,
At the 7:30 AM battle of earlobe creek.
All eyes burn with hatred,
as swords and shields are raised -
All hearts, spilling with valour.

Seconds away,
Sweat drips;
In the wake of the day,
Here comes the blitz!

Suddenly, nothing.
"He must've snoozed it,
Regroup for the onslaught of 7:45 AM!"

[RiverNotch]

Ring, Ring.
The alarm clock's mechanism reverberates; Reverberate is too long a word; weakens the whole impact, for no other reason than to "sound poetic". Something simpler would be better.
An army of sound, Intent on attacking Do you mean to capitalize the "i" and the "a" here?
My ear drum's morning defences, lacking. This rhyme is forced. You don't need it. And the idea of the "ear drum's morning defences, lacking" never becomes relevant or anything to the poem (even regarding the set-up of that last stanza) -- it's just another meaningless modifier you can throw away.
The troops quickly rally, 
As the tumult, heard early, The rhyme here again sounds forced, and the image of the "troops" hearing the sound "early" is too muddy and useless to the image.
Echoes through my ear. Capitalizing the first word of one's lines is so 19th century -- you don't need to do it anymore. 

Clink, clink.
Ear-drum warriors surge together, I was expecting a play on "ear drums" and soldiers marching to the beating of the drums, but oh well. Also, "surging together" sounds redundant -- when an army surges, I believe that already connotes the whole of the group a-moving.
Ready to embrace the banshee's shriek, This is a curious image, since the image has a lot of meaning in the context of the poem (banshee's calls are, if I'm correct, calls of death) -- but then, this sudden hit of clean, mythological symbolism feels somewhat out of place. Keep this, sure, but most of the other lines will have to change.
At the 7:30 AM battle of earlobe creek. Forced rhyme again. "Earlobe creek" -- I'm kinda rattled by that, since one does not hear via the lobes. "AM" breaks the rhythm, and we already know this can't be anything but the morning anyway.
All eyes burn with hatred, I don't feel this. The battle so far has, but for the third line of this stanza, been blandly described -- at this point, I'm not even supposed to know the warriors are all gunless, sword-and-shield-toting men (although the clinking of armor and the big banshee image is a bit, but just a bit, of a hint) -- so the image here ends up meaning nothing to me.
as swords and shields are raised - Could be more. Best, also, if somehow earlier in place.
All hearts, spilling with valour. Same problem as on the fifth line as this stanza. Plus, at this point, you're just telling, not showing: there are a hundred, much bolder ways of singing this aloud.

Seconds away,
Sweat drips;
In the wake of the day,
Here comes the blitz! Since the earlier stanza fell flat for me, there's no tension to be so regarded, here. And the rhyming here still sounds forced, especially with "Sweat drips / ... / Here comes the blitz!", with that last line sounding like something too, er, modern to fit this poem.

Suddenly, nothing.
"He must've snoozed it,
Regroup for the onslaught of 7:45 AM!" Fun ending. "Suddenly, nothing" made me laugh. "Regroup for the onslaught of 7:45 AM", however, just doesn't sound right -- At this point, the commander should be dispersing the men, not asking them to regroup at some far away time, and "onslaught" doesn't sound like a word you'd say to your men in this situation.