For clarity, the first ability should say "until end of turn, other creatures you control get ..."

The second ability confuses a trigger and a replacement effect. Options are "When ~ dies, return it to the battlefield at the beginning of your next upkeep step" or "If ~ would die, exile it instead. Return it to the battlefield under your control at the beginning of your next upkeep."

Elemental Treefolk Warrior

The +1 is way to strong for a splashable three-drop. and two of a single color seems to be the cheapest, no set-up to get mana to +loyalty ability to get a 1/1 with a Chandra and an Elspeth, and at 2/3 it's 3 and two of two different colors with Ashiok, Nightmare Muse. This is also only a rare planeswalker and a not a mythic one.
My suggestions would be either make a 1/1 token and cost , as that's probably okay powercreep over Nissa, Voice of Zendikar or increase the mana value to , keep the token the same, and increase starting loyalty and ultimate accordingly to the increased cost.

If the card text doesn't work without the text, don't italicize it! All italics are supposed to be not rules-relevant: flavor text, reminder text, ability words etc.

Scavenger hunt clearly is relevant. Also ":" is a reserved character on Magic cards for activated abilities. You could word it like this:

• Scavenger hunt for flying – Target creature gains flying until end of turn. (Do this if you control a creature with flying as you cast this spell.)

You accidentally put this rare at common.

The keyword you are searching for is "defender".

Ability words expect you to write out the whole ability.

Capitalization: "Elemental".

Wording: "two cards".

I think, a mana cost on the activation cost of the tokens is in order - you can get a lot of card advantage out of these five tokens.

yeah, I changed the second ability after feedback from my creative partner but I agree that it doesn't feel quite like a common anymore.

You don't pay. Scavenger Hunt is ability that checks for other abilities and if you have the other ability you get a bonus. In this case, if you have a flying creature you can give another creature flying. I appreciate the feedback I will be making a card in the future that explains the ability.

That is the weirdest activated ability. How do you pay "flying"?

That doesn't feel like a common.

The first four words of the flavor text could easily fool you into thinking it's a triggered ability. That entertains me.

Weirdly asymetric as the blue effect creates a feedback loop that allows you to play even more lands.

The ability to play additional lands is weird on a 5 mana value three color creatures, but with that loop makes kinda sense.