To attain 100% completion in The Lost and Damned, the player must accomplish all of the following:

• Complete 23 storyline missions (Clean and Serene to Get Lost).
• Complete 25 Gang War side missions.
• Complete 12 Bike Race side missions.
• Finish Importing/Exporting Bikes for Angus-10.
• Terminate 50 seagulls.
• Find two Random Characters.
• Complete Stubbs' jobs-5.
• Win a game of arm wrestling, pool, darts, and air hockey against anyone.
• Bring Terry or Clay to friendship activities (air hockey, darts, drinking, eating, pool, show, and strip club) at least once.

Rewards

Gives the ability to buy an unlimited amount of ammunition, although it still costs the same as before. NOTE: When purchasing, ex., "Infinite" Rounds of Ammunition for a Pistol, saving, then re-loading that profile, will result in the Numerical Value of Ammunition being lowered to the standard for that particular Weapon. Thus, every time you buy "Infinite" ammunition for a weapon, save, then re-load, you won't have that "Infinite" ammunition from before.