On Grim difficulty, at the start of the level, shoot the 2 zombies in the barricade right at the start then proceed to blow the tank on the other roof. Dispense with the fat ones that survive the blast with powershots, then dash for that first crate. Crates drop random cash from 6,000-30,000. Keep starting new game to get 30,000. Clear the zombies ahead and opening up the chest by the alarmed car. You should have enough cash now to fully upgrade Power for your rifle.
Unlock Morbid and Undead difficulties:
Complete the game under the Grim difficulty setting to unlock the the Morbid and Undead difficulties.
The best defense against these enemies is actually the stock Rifle. Once you get far enough to actually encounter one, you should have fully upgraded the power and rate of fire for it. One power shot and a few extra shots will put this bad boy down fast.
Last Checkpoint of the Graveyard hint:
There are 4 Mouths in this area that scream and summon infinite enemies to attack you. If you don't kill most of the enemies in the previous area (before the checkpoint) there will be too many enemies on screen and when the Mouths scream no extra enemies will be summoned. This makes it far easier to complete this area on Grim and Morbid difficulties.
Easy Does It - Complete Campaign Mode on 'Braindead'.
And So It Begins... - Complete Mission 1 (Any Difficulty Level).
A Trip Downtown - Complete Mission 2 (Any Difficulty Level).
Walk in the Park - Complete Mission 3 (Any Difficulty Level).
On top of the World - Complete Mission 4 (Any Difficulty Level).
Out of the City - Complete Mission 5 (Any Difficulty Level).
Hospital Bill Through the Roof - Complete Mission 6 (Any Difficulty Level).
Gravedigger - Complete Mission 7 (Any Difficulty Level).
Train to Nowhere - Complete Mission 8 (Any Difficulty Level).
Sleeping with the Fishes - Complete Mission 9 (Any Difficulty Level).
Took the Highway - Complete Mission 10 (Any Difficulty Level).
Teamwork - Complete A Mission in Co-Op Mode (Any Difficulty Level).
Survivor - Complete A Mission Without Dying.
Zombie Killer - Kill 1 000 Zombies.
Up Close & Personal - Perform 500 Melee Kills.
Blown To Bits - Blow Up 1 000 Zombies.
Pyromaniac - Burn 1 000 Zombies.
Car Killer - Destroy 500 Vehicles.
Upgrader - Fully Upgrade A Single Slot Of Any Weapon In Campaign Mode.
Suit Up - Collect An Armor Piece.
Contributor - Help Your Country To Clear The Virus Infection.
Mediocrity - Complete Campaign Mode On 'Normal'.
Tough Enough - Complete Campaign Mode On 'Grim'.
Very Dead - Complete A Mission On 'Undead'.
Skilled - Complete A Mission Without Receiving Any Damage.
Zombie Hunter - Kill 10 000 Zombies.
Aim For The Head - Perform 500 Headshots.
Weapons Specialist - Fully Upgrade All Slots Of Any Weapon In Campaign Mode.
Looter - Collect All The Loot In Any Mission.
Morbid Curiosity - Complete Campaign Mode On 'Morbid'.
Double the Action - Complete Campaign Mode in Co-Op Mode.
Genocidiary - Kill 53 596 Zombies.
Top Gear - Collect All Armor Pieces.
King Of Looters - Collect All The Loot In Every Mission.
Romero Would Be Proud - Earn all Bronze, Silver, and Gold trophies.
"Road Of Devastation" trophies:
Still In the Game - Survive to Round 5.
Dynamic Duo - Complete a Round in Co-Op Without Either Player Taking Damage.
Found 'Em - Find all the Egogate emblems.
Keep It Up - Complete a Round with a Kills-per-minute ratio of 100 or more.
Combo Master - Get the Apocalypse Combo Kill Bonus (150 Kills).
Never Give Up - Survive to Round 10.