OK I haven't played since 4th Edition so I might be prototyping these wrong, but I read the 9th rulebook to get a better idea.
This is the Black Magic spell list from the Final Fantasy series. I might have gotten some of the balance wrong as far as costs go.
New rule: Power Word x
When announcing a spell of type Word, you may pay an additional cost and reveal x cards sharing a color with that spell from your hand. If you do, you may add an additional effect to the spell. Multiple Power Words can be added to the same spell, but the same Power Word cannot be added more than once, and each activation of a Power Word on the same spell must reveal a different card.
Blind (W)
Instant - Word
Target attacking creature deals no combat damage to other creatures this turn.
WW, Power Word 1: Choose any number of attacking creatures instead.
Blizzard (U)
Sorcery - Word
Deal 1 damage to target creature.
U, Power Word 1: Also, tap that creature.
U, Power Word 1: Deal 3 damage instead.
UU, Power Word 1: Choose up to twice as many target creatures. This Power Word can be activated multiple times.
Fire (R)
Sorcery - Word
Deal 2 damage to target creature.
RR, Power Word 1: Deal 5 damage instead.
RR, Power Word 1: Choose up to twice as many target creatures. This Power Word can be activated multiple times.
Poison (B)
Sorcery - Word
Put two disease counters on target creature. During that creature's controller's upkeep, remove a disease counter to put a -0/-1 counter on that creature.
B, Power Word 1: Double the number of disease counters. This Power Word can be activated multiple times.
BB, Power Word 1: When a disease coutner is removed, place a -1/-2 counter on that creature instead.
Sleep (U)
Sorcery - Word
Target tapped creature does not untap during its controller's next untap step.
UU, Power Word 1: Choose up to twice as many target creatures. This Power Word can be activated multiple times.
Thunder (R)
Sorcery - Word
Deal 1 damage to target creature.
R, Power Word 1: If that creature has flying, deal an additional 2 damage to it.
RR, Power Word 1: Also destroy up to as many target artifacts as this spell targets creatures.
RR, Power Word 1: Choose up to twice as many target creatures. This Power Word can be activated multiple times.
Dark (B)
Sorcery - Word
Deal 2 damage to target nonblack creature.
BB, Power Word 1: Choose up to twice as many target creatures. This Power Word can be activated multiple times.
BBB, Power Word 3, discard your hand: Instead, destroy all nonblack creatures. Those creatures can't be regenerated.
Element Spikes (1W)
Enchantment - Word Aura
Enchant creature.
When this creature receives combat damage, Element Spikes deals 1 damage to that damage's source.
R, Power Word 1: Element Spikes deals an additional damage.
U, Power Word 1: Element Spikes deals an additional damage.
B, Power Word 1: Element Spikes deals an additional damage.
G, Power Word 1: Element Spikes deals an additional damage.
Lock (1G)
Enchantment - Aura
Enchant creature.
0: Enchanted creature must block this turn if able.
Rasp (1U)
Instant - Word
Tap up to two of target player's target lands, then empty that player's mana pool.
Power Word 1: Gain 1 mana of the appropriate color for each basic land tapped in this way.
UU, Power Word 1: Tap up to two additional target lands.
Water (U)
Sorcery - Word
Deal 1 damage to target creature, or prevent the next 2 damage that would be dealt to target blue creature.
UU, Power Word 1: Deal 3 damage instead.
UU, Power Word 1: Deal or prevent twice as much damage.
UU, Power Word 2: Target all blue creatures instead.
Zombie (1B)
Enchantment - Aura
Enchant creature.
Enchanted creature is of type "Zombie" and has "B: Regenerate this creature".
Debarrier (G)
Instant
Destroy target Aura.
Curse (BB)
Enchantment - Word Aura
Enchant creature.
Enchanted creature loses all card text. (it still keeps name, casting cost, types, expansion, power & toughness, artist, and artwork)
B, Power Word 1: In addition, enchanted creature cannot use abilities granted to it by other effects.
Stone (G)
Enchantment - Aura
Enchant creature.
Enchanted creature loses its color and gains the type "Artifact".
Flare (1RR)
Instant
Deal 4 damage to target creature or player. Effects that prevent or redirect damage canot be used to prevent this loss of life.
Quake (1GG)
Sorcery
All creatures without flying take 3 damage.
Toad (1U)
Sorcery
Return two lands you control to your hand: Remove target creature from the game. That creature's controller gets a 0/1 green Toad token creature.
Meltdown (1UR)
Instant
Target spell cannot be countered, and damage inflicted by it cannot be prevented or redirected.
Ultima (WUBRG)
Sorcery
Remove all creatures, artifacts, and enchantments from the game. Each player takes 1 damage for each card he or she controls removed in this way.
