In Fellowship Block, one of the strongest strategies was building a fellowship of a few companions loaded to the gills with Possessions and other permanent cards. It's brainless, pretty stale and not at all good for competition, so by TTT, Decipher tried to punish companions from being overloaded.
Grima, Wormtongue was the strongest of these, but
Vengeance was another example. I think it's perfectly fine: the only card it feels a bit harsh on is the Ringbearer, but a lot of the time the pump will do nothing.
Kill them Now is probably more consistent as a pump for trackers.