While you're playing a random match and you've a character with a long and boring Blazin'Special, press start 2x and a Blazin'Song is activated. Note: I use this only for boring and long during specials.
Full skills
With story mode you can upgrade Tank, Briggs, Proof and Spider, to get all the skills of these guy's you only have to clear the survival mode. You'll have to face 37 enemy's at maximum. If you finished it you'll get 100.000$ which you can use to upgrade the guy's. Hint: every time you finish D-mob ( with a submission or K.O.) you get 100.000$, so you can upgrade the next person.
Easy way to get new skills
Here's an easier way to get all your skills. Do a story mode with all four characters but stop at the very last round when you face D-Mob. Do this with all four characters and then when the all on the last round finish the story mode. After all those fights you should have enough cash to get every bodys full skill.