Chakram Slinger

Partner with Chakram Retriever (When this creature enters, target player may put Chakram Retriever into their hand from their library, then shuffle.)
{R}, {T}: This creature deals 2 damage to target player or planeswalker.

Battlebond Promos

Battlebond

Partner with Chakram Retriever (When this creature enters the battlefield, target player may put Chakram Retriever into their hand from their library, then shuffle.)
{R}, {T}: Chakram Slinger deals 2 damage to target player or planeswalker.

A nonlegendary creature can’t be your commander, even if it has a “partner with” ability.

Chakram Retriever’s last ability resolves before the spell that caused it to trigger.

Note that the target player searches their library (which may be affected by effects such as that of Stranglehold) and that the card they find is revealed, even though these words aren’t included in the ability’s reminder text.

Players can cast spells and activate abilities after Chakram Retriever’s last ability resolves but before the spell that caused it to trigger does.

“Partner with [name]” represents two abilities. The first is a triggered ability: “When this permanent enters the battlefield, target player may search their library for a card named [name], reveal it, put it into their hand, then shuffle their library.”