You may have Sakashima enter as a copy of another creature you control, except it has Sakashima's other abilities.
The "legend rule" doesn't apply to permanents you control.
Partner (You can have two commanders if both have partner.)

Spells and abilities your opponents control can't cause you to discard cards or sacrifice permanents.
+1: Choose a nonland card name, then reveal the top four cards of your library. Put all cards with the chosen name from among them into your hand and the rest into your graveyard.
−3: Return target card from your graveyard to your hand.

: Add .

Whenever a creature you control dies, each other player sacrifices a creature of their choice.

Landfall — Whenever a land you control enters, put a +1/+1 counter on target creature.
: Double the number of +1/+1 counters on each creature you control.

Creatures you control get +1/+1 and have deathtouch.
When this enchantment enters, if it's your main phase, there is an additional combat phase after this phase followed by an additional main phase. When you next attack this turn, untap each creature you control.

As The Black Gate enters, you may pay 3 life. If you don't, it enters tapped.
: Add .
, : Choose a player with the most life or tied for most life. Target creature can't be blocked by creatures that player controls this turn.

: Add .
: Target 1/1 creature gets +1/+2 until end of turn.

: Add .
: Add or . This land deals 1 damage to you.

Legendary creatures you control get +2/+1 and have ward .
Nonlegendary creatures you control get +1/+1.

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Creatures you control gain flying, vigilance, and double strike until end of turn.
• Creatures you control gain lifelink, indestructible, and protection from each color until end of turn.

: Add .
: Add or . This artifact deals 1 damage to you.

: Counter target green spell.

+2: Look at the top card of target player's library. You may put that card on the bottom of that player's library.
0: Draw three cards, then put two cards from your hand on top of your library in any order.
−1: Return target creature to its owner's hand.
−12: Exile all cards from target player's library, then that player shuffles their hand into their library.

(: Add .)

Untap all permanents you control during each other player's untap step.

As this creature enters, choose a player.
This creature has protection from the chosen player.

Target player draws two cards.
Flashback—, Pay 3 life. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

If one or more creature tokens would be created under your control, that many 4/4 white Angel creature tokens with flying and vigilance are created instead.

: Prevent the next 1 damage that would be dealt to target creature this turn.