A commander deck should run around 10 to 15 instants
These decks are usually built to have longer games as your opponents burn through cards before you are able to set up your chains of cards
If you want to commit even harder to the wraith typal theme, changelings are a great place to start with Black Market Connections, Changeling Outcast, and Maskwood Nexus
Roughshod Duo enables both aggressive raccoon and mice decks, for example, while Lightshell Duo fills the graveyard for rat decks and plays well with the spells otter decks depend on
This allows players to deploy massive, expensive boss monsters several turns ahead of schedule
Master of Cruelties A niche card folks might not be aware of, Master of Cruelties does work in Rakdos decks that can easily ping you for the last life