Just don't use them for double-sleeving
Like Overprotect its really a modal spell that is a combat trick or a saving spell, but thats great and sometimes you end up using both modes at once, and it feels great
Save up rare and mythic wildcards : Almost all Standard decks require a high number of rares and mythics to craft, so saving wildcards up until youre able to invest in one of those decks and get it in one go is well worth the wait
It might not be as strong as Blighted Agent, but playing this on turn 1 into two Might of Old Krosas and a Mutagenic Growth have enabled many a turn-2 kill, and its solid even without the nuts
Then, he can use his ability Cheer, which allows you to draw and card and add a counter to another creature when a creature with a counter attacks
There are plenty of one-time kill creatures, such as Ravenous Chupacabra , Noxious Gearhulk , and Shriekmaw , but also some repeated-use kill creatures like Royal Assassin , Avatar or Woe , and Guul Draz Assassin