Personal Note: I had an incredibly hard time getting the Med Bot and Nonsensical Sacrifice to activate. It took me several hours of Co-Op play to eventually get it to happen. I was almost at the point of researching any known glitches regarding it. Just be patient and eventually you will get it. It helps if you and your teamates are damaged or someone is in Fight for your lifeAll credit goes to AbsolutioN IX on Trueachievements for writing this
You can get this starting at level 25 on Claptrap. There are 15 total modes that Claptrap can use in Vault Hunter.EXE. The game analyzes your stats and picks a mode when you press LB, but in my opinion, most of them are random.
Claptrap has 9 available from the start, which are:
-Funzerker (Dual wield weapons)
-Shhhhh... Trap (Turn invisible)
-Miniontrap (Throw down turret)
-Blightbot (Send out a flying claptrap with fire/corrosive damage)
-Mechromagician (send out flying Punkbot, which distracts and melees)
-Meat Unicycle (Melee weapon with sawblade)
-Rubber Ducky (reflect bullets and bounce)
-Med Bot (shoot laser at teammates to heal them)
-Nonsensical Sacrifice (revives teammates that are currently down at the cost of your own life)
NOTE: Med Bot and Nonsensical Sacrifice are more likely to show up if you have teammates injured or down. (Downed teammates seem to be a requirement for the latter)
6 abilities can be unlocked by putting points into Claptrap's skill trees. There are two abilities in each tree:
Boomtrap: (Left Tree)-Torgue Fiesta (Rapidly throws out grenades) Put a point into I Am Rubber, You Are Glue.
-Pirate Ship Mode (Cannons appear in four corners of your screen and fire) Put a point into Livin' Near the Edge.
I Love You Guys!: (Middle Tree)-Clap-in-the-Box (Claptrap holds a bomb that detonates) Put a point into Kick Him While He's Down.
-Gun Wizard (greatly increases fire rate and reload speed for team) Put a point into You're.. GOING TO LOVE ME!!
Fragmented Fragtrap: (Right Tree)-One Shot Wonder (gun magazine will empty with one shot) Put a point into Tripleclocked
-Laser Inferno (disco ball will fire lasers at enemies) Put a point into Rainbow Coolant.
While attempting this, you can re-spec your points to switch from skill tree to skill tree. You can do this at the Quick Change station just outside the bar in Concordia.