Attack!

What are the implied/stylistic differences between oppugnare, aggriedor, and that one meaning of petere?

Literally:

oppugno, -are (ob against pugare to fight) - to fight against
aggredior, -gredi (ad towards [/i]-gredi[/i] to step) - to step towards; hence: to advance/assail
peto, -ere - to chase after, so… to pursue, attack