Council of Elrond

Come At Need
Hazard Long-Event
If a companion controlling an ally faces an attack, at least one ally that companion controls must tap to support the companion.

what's the intention of this card?
why should anybody play it?
it doesn't seem good to me? or is it against a special strategie?

It taps the ally, which causes it:

A) to face a strike later on in the turn
B) to cancel its special ability
C) to prevent its use with cards like Marvels Told, etc etc

The things this can prevent is Tom Bombadil taking all strikes untapped without any problem, disabling Regiments when the limit is low and you dont want to see a creature bounced, seeing Treebeard marvel around without any cc, by example.

but I still would make it permanents, because it would be too bad without...