Regarding the Achievements List.
Want to get these achievements easy? After you have beaten the game once and unlocked the "Infernal" difficulty, make your way to the Malebolge stages. On the first stage, you have unlimited mana, so equipt your "Sins of the Father" spell, and start using your cross attacks to build your combo meter up to 200 to unlock the "Masterpiece" achievement.
Poetry in Motion requires you to get a whopping 666 hit combo. for this one, I used the Siminists (sp?) round. It's the "Air Kills" level. now, first off, I wantyou to go on and set your difficulty to Infernal, because your enemies are more resistant to attacks, and your attacks do less damage. All you have to do now is litterally press "B" and use cross attacks until you see "Poetry in Motion achievement unlocked" across your screen. I recommend that you have the "Memory of Acre" relic, which makes you uninterruptable whilst doing cross attacks, and the "Coin of Plutus" relic, which increases the combo window. Dante auto targets enemies for cross attacks, so don't worry about aiming at enemies.
Good Luck, and Godspeed!