Portable holo-pedestal
From Halopedia, the Halo wiki
The Covenant's Holo-Pedestals are basically the Covenant versions of the UNSC's Holotank. They are small, cylindrical pedestals that create holographic fields. They can be used to create holographic maps to find the quickest route to a destination or by AIs to give themselves a holographic "body". AIs can also access the map data from the pedestal's link to the Covenant information network and give directions verbally to anyone near the pedestal. Cortana enters one to gain access to info in High Charity on the level Gravemind, remaining there for the rest of the game. In Halo 3 they are frequently used by the Prophet of Truth to deliver speeches to the Covenant, right up until his death (In Halo 3 they are destructible).
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Appearances
Halo 2: They appeared mostly in the levels Delta Halo and Regret.
Halo 3: These can be seen on quite a number of levels, including Tsavo Highway, The Storm, The Ark and The Covenant.
