Damage and pump

[Magician]

When does burn damage wear off. Say I pyroclasm at the beginning of my turn and then attack later, they block. Would the damage stack?

My friend attacks and I block. Can he then play a giant growth or what not, after I block? Thanks

[Wallace]

Damage stays on creatures until the end of the turn or the creature regenerates.

You can attack, your friend chooses blockers, then you can play instant spells before combat damage goes on the stack. The blocking play will also have a chance to play spells before damage. After damage goes on the stack both palyers will have another chance to play instant spells. Damage resolves...enter the second main phase.