Heal (original)

Heal was a priest healing ability, learned by Holy and Discipline priests at level 28. It covers the niche of a cheap heal that can be cast virtually forever. The downside is that it is slow to cast and not very powerful. For a far more powerful but less efficient healing spell, use Greater Heal. In situations where speed takes priority over mana efficiency, the quick but expensive Flash Heal may be preferred. While both these spells are undeniably more powerful, Heal is more mana efficient, and is a spell that can be used as a filler when nothing much else is going on.

Warcraft III Manual background
''The positive energies of the Light can be channeled to create a healing energy wave. This technique, developed first by the high elves, and later taught to humans, has remained relatively unchanged since its original discovery.''

Strategies

 * Heal is designed as a cheap and spammable filler spell, designed to counter light damage without denting your manabar much.
 * Heal can proc the talent From Darkness, Comes Light. The free Flash Heals may offset that Heal is not a heavy hitter.
 * If you pick the Power Word: Solace talent, you may get more out of your mana by casting Greater Heal and using the downtime regaining mana through Solace, rather than chaincasting Heal.


 * Discipline priests can use Heal to proc and maintain Grace cheaply.
 * Discipline priests can make Heal an attractive option due to Strength of Soul (priest ability) reducing the Weakened Soul debuff on targets. With its low cost, regular Heal casts can allow the priest to use Power Word: Shield more often, saving mana, benefiting from Haste (Borrowed Time (priest ability)) and preventing spellcasting from being interrupted.


 * Holy priests using Chakra: Serenity will cast Heal at +15% strength.
 * Holy priests using Chakra: Serenity can refresh the duration of Renew on targets by using Heal (or any other direct heal). One less commonly used strategy for very cheap AoE healing is to cast Renew on up to 5 targets and rotate Heal on each of these to refresh the duration of the HoT. This strategy doesn't allow much room for mistakes, but it can be used to keep a small group of people alive virtually forever as long as the damage isn't too heavy.
 * Combined with the Holy Word: Serenity healing spell and Chakra: Serenity, this spell is often enough to outheal tank damage in leveling dungeons and some heroics, meaning less dependency on the more expensive healing spells.