This means that they can then only tap for Red mana - and if your opponent doesnt even have Red in their deck, it could well win you the game on the spot
Shifting Ceratops Shifting Ceratops is a pretty powerful dinosaur in combat
Osgir is a commander I really want to build because it actually does something cool with artifacts without requiring all the ridiculous blue artifact design mistakes support cards that tend to make games of Commander more toxic than anything else
Sword of Truth and Justice is certainly strong within a counters or planeswalker-based deck, but even then I question if I want to be paying the five mana to achieve the effect
Honorable Mention Hashaton, Scarab's Fist Let's start with this two-drop blocking 1/3 size guy for Orzhov mana, and then when you discard that dork you can spend three mana one of which is Blue to make a tapped token copy of it at 4/4 size and a Zombie too
You must still pay all costs and follow any timing restrictions and permissions for artifact spells you cast from your graveyard this way