Spiritmonger / Reaper of the Wilds I like beefy gold creatures that are cheap, on-curve, and have at least three abilities
For example, this means that normally, if you control Hunting Velociraptor, you can cast Grim Giganotosaurus for its prowl cost only if a Dinosaur dealt combat damage to a player, but if an effect causes the spell to have other creature types, the prowl ability is also satisfied by a creature with those additional types having dealt combat damage to a player
1 Yenna, Redtooth Regent Yenna, Redtooth Regent's Commander deck can use its enchantment-copying ability to slow down enemy creatures with Auras like Darksteel Mutation and Song of the Dryads, but its best cards are more proactive
Using a double flicker target spell, you can get back not just your flicker spell, but something else
A card like Gollum, Scheming Guide is just fun as your commander