Visit Slim Cognito's is an optional mission in Up Your Arsenal, taking place in the Deep Sea Hideout, Aquatos. Slim Cognito contacted Ratchet and Clank three times to encourage them to return to his hideout and purchase new Megacorp weapons.
Slim Cognito will contact you three times at the start of missions on other planets about new weapons. First, during "Find Captain Qwark" on the Thran Asteroid Belt, you will be contacted about the Bouncer. This is an especially useful weapon that fires one bomb which then explodes into smaller, mini bombs that damage nearby enemies, making it useful both against clusters of medium enemies and larger enemies. It costs 150,000 bolts. As it is versatile and effective in all circumstances, it is worth purchasing. If you have a Going Commando save, you will obtain it for free.
Slim contacts you again at the start of "Get inside command center" on Koros, informing you about the Plasma Coil. This weapon hits a target and then immediately damages nearby targets, once again making it useful both against clusters of medium-sized enemies and larger enemies. It costs 250,000 bolts. Return to Slim if you can afford it, or if you have a Going Commando save.
Finally, at the start of "Battle your way to the launch site", Slim contacts you about the Shield Charger. This is a purely defensive weapon that generates a shield around you once active, which protects you from all damage until enough damage is dealt to the shield. It is very useful for the final mission due to the strength of the enemies. The Shield Charger costs 250,000 bolts. Again, return to Slim if you can afford it, or if you have a Going Commando save.