Resources

Magic: The Gathering Oracle Changes

Planar Chaos to Future Sight (Single Change View)

Changes involving "cumulative upkeep"

Old card (Planar Chaos) New card (Future Sight)

Heat Wave

{2}{R}

Enchantment

Cumulative upkeep {R}

Blue creatures can't block creatures you control.

Nonblue creatures can't block creatures you control unless their controller pays 1 life for each blocking creature he or she controls.

Heat Wave

{2}{R}

Enchantment

Cumulative upkeep {R} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)

Blue creatures can't block creatures you control.

Nonblue creatures can't block creatures you control unless their controller pays 1 life for each blocking creature he or she controls.