If Thousand-tailed Watcher reduces a unit's power, and that unit later receives a power buff during combat, does the Watcher's effect continue to reduce the buffed power or was it a one-time reduction?

Ruling: The Thousand-tailed Watcher applies a one-time reduction that lasts the entire turn, not a persistent effect. If a unit later receives a power buff, that buff is added to the already-reduced power.

Sequence:

• Thousand-tailed Watcher reduces the enemy unit's power by 3 (from 2 to -1, but minimum 0 or stays at reduced value)
• During combat, opponent plays a spell giving +1 power
• The +1 is added to the current reduced power
• Both units die in combat (2 might vs 2 power)