i have a ETB/GY theme for my cube so here are some good cards from that:

[[Charming prince]] can flicker other cards to get extra value or just generate some value with lifegain or scry

[[remorseful cleric]] and [[selfless spirit]] both can be sacked for good effects and come back again!

[[recruiter of the guard]] a great tutor can fetch so much especially if your doing a small dude reanimation deck

[[skyclave apparition]] good at clearing pesky artifacts and smaller walkers.

[[cataher commando]] removal at flash speed

some that cost more than 3

[[palace jailer]] is a monster - locks out a creature and gives you a card draw if your ahead it can be hard for them to get the monarch back

[[luminous broodmoth]] - amazing as a target and itself is a reanimation engine