PSP Games

Final Fantasy Type-0
Valkyria Chronicles II&III(and I on PS3)

And for those of us who don't speak Japanese, Type-0 fan translation is nearing completion and Valkyria Chronicles III translation was recently released =)

FlatOut: Head On

Patapon 1,2,3
Corpse Party
Hakuoki

GTA China Town Wars. One of the best GTA. Ever.

obviously "Monster Hunter Freedom Unite/2nd G" or import "3rd G" from japan and use the english translation plugin (almost finished translation), if you don't speak japanese. (the plugin needs the PSP to be hacked, tho)
3rd G is very similiar to Tri(Wii) and 3G ultimate(3DS/Wii U).

if you're into Final Fantasy, get your fanboy/girlism serviced with "Dissidia" or the milking cow "FFVII Crisis Core"

Dante's Inferno is also a nice PSP port for it's 360/PS3 counterpart, if you're into hack 'n slay.

• Patapon series

• Monster Hunter: Freedom Unite

• Dissidia Final Fantasy (only if you're fan of Final Fantasy)

• Kingdom Hearts: Birth by Sleep

Patapon series
Monster Hunter: Freedom Unite
Dissidia Final Fantasy
Kingdom Hearts: Birth by Sleep
Final Fantasy Crisis Core
Metal Gear Solid Peace Walker
God of War series

Crisis Core: Final Fantasy VII is honestly my favourite PSP game. I may be biased due to being a FF fan but I really loved the game (it's where my DP comes from). Other games I can recommend are:

• Kingdom Hearts: Birth by Sleep
• Dissidia or Dissidia 012, which is sort of an extended remake.
• Gods Eater Burst
• Valkyrie Profile: Lenneth, which is the remake of Valkyrie Profile originally on PS1.
• Final Fantasy IV Complete

Buy Model: PSP 3000 , PspGO sucks !!!!
You can also emulate other consoles, remember that.

GTA, Assassins Creed: Bloodlines, Gran Turismo(4 players wlan), socom great games and got PSP 2000 its fine. PSPGO SUCKS 100%

I used Custom Firmware for my PSP, Its a good idea for an aging console, look into it :)
Metal Gear Solid: Peace Walker
Valkaria
Monster Hunter Freedom Unite,
GET THESE!

Ace Combat on PSP was awesome!
Pirates! too.

Damn i played so much on the little thing but cannot remember anything lol

Didn't notice Jeanne de Arc yet.

Steambot Chronicles was fun for me

WWE SVR 2006-08, tekken 6, gow ghost of sparta and chains of olympus, powerstone collection ,street fighter alpha 3 max,megaman powered up, need for speed most wanted, , tons more too, From psp selling experience i recommend 1000 series for easy modding , cheaper and a bit bulky but good , or the early psp 2000, for ex , star wars, silver daxter , gow psp , try to avoid getting a black slim .

1. BreakQuest (Best arcanoid on PSP, I think)

2. Tony Hawk's Underground 2 Remix

3. Worms: Battle Islands

4. GTA VCS and LCS

5. Dungeon Siege: Throne of Agony

6. Prince Of Persia: Revelations

7. Manhunt 2 (Because of no first one on PSP)

8. Tom Clancy's Splinter Cell: Essentials

9. PSX games.

Both God Of War games. Some of the best games for PSP.
Daxter.
GTA Chinatown Wars - the best for PSP.
Prince Of Persia WW and TT. (they have other names for PSP but i can't remember them)
Siphon Filter.
Monster Hunter.
Dante's Inferno. (i liked it, stfu)
All Metal Gear Solid ones. I belive they were 2 or 3 on the PSP.
Patapon
Lumines 1|2 - great time killers
Kingdom Hearts (i didn't play any of them but people say they are awesome)

Also, alot of the classics have games on the PSP, like Megaman, Castlevania, etc.