This is a budget deck upgrade for Lifeline, the Selesnya (G/W) Starter deck on MTG Arena unlocked through the Color Challenge.

This Deck Upgrade costs: 8 Common WC's || 8 Uncommon WC's || 0 Rare & Mythic WC's
All other cards in the deck, including the rares and mythics, are obtained for free from the other Arena Starter Decks.

The main goal of the deck is to create multiple large threats by using lifegain as scaling. The upgrades were aimed at making the deck more synergistic, aggressive, and efficient. Let’s talk about a few of the themes and our upgrades.

LIFEGAIN ENABLERS

This deck’s strategy is built around the lifegain theme, so we need two things: enablers and pay-offs. We added in some more enablers to make our deck faster and more consistent.

 4 of Soulmender because it is a great way to reliably gain life each turn for all of our pay-offs and it keeps itself safe by not having to attack for us to gain life. Please note that this card is part of the Arena Basic Set and thus is only available in Standard BO1. Prosperous Innkeeper is also a reliable way to gain life without having to attack. As an added bonus, it can ramp you or fix your colors with the treasure token. We bumped up this card to 4 copies because it’s so strong for our strategy. Priest of Ancient Lore is also reliable life gain (See a pattern here?) that also draws us a card. It does everything we need it to and even though the body is weak we're mostly playing it for the effect.

LIFEGAIN PAY-OFFS

We’ve got a lot of life-gain pay-offs because we want to make sure that if we’re going to be gaining life we are rewarded for it. These cards are the ways that we win games, so we want to have a decent balance of our pay-offs and our enablers in our starting hand.

Cleric Class An enchantment for W that you can upgrade for 3W and then 4W to give you some very strong effects, this card is a huge pay-off for us. It’s Level Two turns each of our creatures into a Hallowed Priest, so even if we don’t draw our pay-offs, Cleric Class can turn our enablers into pay-offs by stacking +1/+1 counters on them. It gives us even more gas at Level 3 by reanimating something from our graveyard and gaining us life equal to its power. We bumped this card up to 4 copies. Hallowed Priest and Trelasarra, Moon Dancer do essentially the same thing, with Trelasarra being a slightly stronger version. 1W and GW respectively, they gain a +1/+1 counter every time we gain life, and Trelasarra even gives us a scry to boot. These guys can get out of hand quickly with how fast we can gain life in this deck and hopefully overrun our opponent before they are able to deal with them. We run 4 copies each because they are our main threats. Please note that Hallowed Priest is part of the Arena Basic Set and thus only available in Standard BO1.

REMOVAL

We replaced Devouring Tendrils with Blizzard Brawl because it's a stronger and faster effect. With how aggressive our strategy is it's more important for our removal to cost 1 mana than for it to also gain us a bit of life. The indestructibility is also nice. 

POTENTIAL UPGRADES

From this point on, there are many available paths you can take when upgrading the deck. You will likely encounter many different versions, whether of similar or varying power levels. Since it is a budget deck, I have provided a list of strong cards that would improve the deck, although they are not all meant to go in together. Hopefully this will give you some flexibility in upgrading your deck as you progres through the game and open packs. The best place to start is usually lands. 

CONCLUSION

I hope you enjoy this deck and that it serves you well. There's a deck tech video on youtube attached to this guide and I stream on Twitch here so don't hesitate to reach out :) I'd love to hear your experience with the deck. Good luck and have fun!