From Populous Wiki

Mana Required : 50 000
Shots : 4
Range : 8
Duration : 2 minutes
Incantation : Sethanko
If you cast this on your followers and your followers only, they will become invisible for the 2 minute duration of the spell. This spell will broken if your unit should attack any of the enemy tribesmen or their buildings.

You can track invisible enemy units by closely watching the footsteps they leave on the ground.

Note: Does not affect your shaman. Note: Invisible followers can still be converted by enemy preachers, even though the enemy can't see what they're converting. Note: Angels of Death can track and eat invisible units. Note: Invisible enemy followers are revealed on the minimap when near guard towers.

Standard Spells: BurnBlastConvertSwarmInvisibilityMagical ShieldLandbridgeLightningHypnotiseTornadoSwampFlattenEarthquakeErodeFirestormAngel of DeathVolcano
Guest Spells: BloodlustTeleportArmageddon
Multiplayer Spells: Ghost Army
Forge World Spells: FlattenLandbridgeErodeHillValleyRaiseLowerWildmenTrees