Shouldn't the double strike thing be an "instead" since having both is redundant? Also Panda reads strangely to me.
Have you ever experimented with doing Menace and Deathtouch with Mack? Could go that route then reserve First Strike/Pingstrike for Panda:
>Clownface
"Whenever ~ attacks, put a knife counter on it. As long as it has one knife counter on it, it has deathtouch. As long as it has two or more knife counters on it, it has menace.
1BR. T, Remove a knife counter from @: Destroy target creature."
>Panda
"Whenever ~ attacks, put a gun counter on it. As long as it has a gun counter on it, it has first strike. As long as it has two or more gun counters on it, it has "Whenever @ attacks, it deals 3 damage to target creature."
2R, T, Remove a gun counter from @: @ deals 3 damage to target player."
I dunno, just a thought. I don't expect you to use any of this. The upside is you might be able to make Panda cheaper going this route, but I dunno about Clownface.
I feel like this should follow the themes of your Amazon stuff more. Like, when you manland it, you get to attach an Equipment or Aura you control to it or something. Actually, making it so you can attach an Aura from your hand without paying its mana cost could be cool since when it stops being a creature the Aura falls off so it basically turns Auras into combat tricks. Just an idea. As it is, it seems fine though, if you want to keep it simple, which isn't a bad thing.
Not a bad idea to make it deathtouch. I could make it a 2/4 maybe... not sure if that's too much toughness though.
>breaks NWO
The "four lines is too much" thing feels arbitrary to me, but yeah, as they are, it breaks the red-flagging rules. I mean it can still exist, but it'd take up a slot. The 4-line rule really bones cards that have drawbacks and benefits, like that one.