These creatures are often simply referred to as efficient a short hand way to say that they are good values for their cost
You ideally dont play this grumpy Gruul card unless youre drawing three or four cards, but you could do worse than a 5/5 Exploration
The goal was to self-bounce and recast your things to trigger ETB things (Mulldrifter), self-bounce things (Azorius Aethermage), leaves play things (Circuit Mender), cast things (Equilibrium) and tapping the dork for something valuable (Opposition), with a bounce of self-bounce (Erratic Portal) and a flicker backup theme (Far Traveler proper) in order to lean into the non-cast stuff
There are enough legendary creatures that synergize with out theme that Colonel Autumn is a solid pick to represent this line
The burn effect is good at closer games as well and the discard effect can come up if you have a hand of cards you want in the graveyard
Secret Lair has been letting the Magic designers be especially creative, and that's something to appreciate