Vadrik gives you a discount on your instants and sorceries equal to its power, and it gains a +1/+1 counter whenever it becomes day or night
Whenever you attack with one or more Creatures, you can add that much mana using any combination of Red and Green, and that mana doesnt empty from your pool until end of turn
Six mana to copy a creature you control is a lot, but as someone who plays a Kiki-Jiki, Mirror BreakerKiki-Jiki, Mirror Breaker deck, I cannot express enough how amazing it is to copy your most powerful creature over and over again
These have been around since Dark Ascension and have cropped back up in almost every set featuring double-faced cards, but now theres a commander that wants you to put them all in the same deck
Prismatic Ending and Lightning Bolt, however, are both essentially bulk