Hours 'Til Morning is the last stage of Sports Night.
Battleground
The battle starts with a few Pigge Backs, followed by some Zrocos. After the base is hit, Lord Gravey will spawn with a shockwave along with Dead Donny Dash, Zir Zeal and Pigges.
Lord Gravey and Zir Zeal serve as the main threats of this level.
Strategy
Strategy 1 (ft. Sarukani, Orbital Platform Armageddon and CAT-6 Siege Engine)
ITEMS: Rich Cat(make things easier)
Row 1: Corrupted Psychocat*", Weedwacker Cat, Ectoweight Cat, Elemental Duelist Cat, Sarukani(first form)^,
Row 2: Housewife Cat, Cataur*, Piledriver Cat, Orbital Platform Armageddon^, Cat-6 Siege Engine(important).
First, earn money and stall the Pigges with one Elemental Duelist Cat. When you have enough money, spawn Cat-6 Siege Engine. Start spawning all in first row(their role is protecting Cat-6 Siege Engine and debuffing zombies). Cataur and Piledriver Cat should be released, too. Don't stop spawning, and you'll win! Enjoy your 1-2 Lucky Tickets G!
(*) - With "Target Zombie" talent(Cataur - with Z-kill, too).
(") - With "Weaken" talent.
(^) - You may not bring them, but they're helpful.
Strategy 2 (ft. Polevaulter Cat)
Line up: 3 meatshields(for example Eraser Cat, Crazed Wall Cat and Jiangshi Cat), Polevaulter Cat/Housewife Cat, another anti-zombie cat(Weedwacker Cat preferred), anti-red cats(Crazed Whale Cat, Island Cat etc.), ranged attackers(Crazed Sexy Legs Cat etc.) and fast units(Crazed Giraffe Cat etc.). A.Bahamut and Ururun Cat are optional.
This level is relatively tame compared to the previous stage, Fallen Priest. The only problems being Lord Gravey blocking your heavy hitters from destroying the base and Zir Zeal and Dead Donny Dash (zombie Leggsy) disrupting your backline and ranged attackers.
Start with some anti-red and meatshields to stall the Pigge Backs and save some money, after the Pigge Backs are dealt with, start sending in anti-zombie cats(e.g. Polevaulter Cat), meatshields and ranged attackers towards the base. When the boss spawns, send in A.Bahamut and fast units when both the Zir Zeal and Dead Donny Dash are burrowing to clear the Pigges and get a few hits on Lord Gravey.
Now, you want to make sure to stack as many Polevaulter Cat and antizombie cats as possible so it'll become likely for them to last hit the zombie enemies, hence trigger the zombie killer ability. This is where Polevaulter Cat shines: She has shorter standing range than Dead Donny Dash and longer standing range than Lord Gravey. Since Dead Donny Dash doesn't dig very far from the enemy base if you have a fast unit when the shockwave hits, ideally Polevaulter Cat can get into the blind spot of the zombie LD Leggsy as well as be able to support A.Bahamut by slowing Lord Gravey using her Long Distance ability without being knocked back.
The only thing you need to watch out is the Zir Zeal, as it can stop literally every unit in your lineup. Allowing Dead Donny Dash to snip your units, so kill them Zir Zeals as fast as possible(even better if it is a Zombie killer kill).
After the Zir Zeals and Lord Gravey are dead, you are free to attack the base as the other enemies in this stage can't do anything to stop you.
If you have Weedwacker cat(Gardener TF), then this stage becomes very easy because he can constantly freeze the zombie enemies, and eventually(hopefully) trigger the zombie killer ability so that you will never deal with them again.