This deck is a variation of the mono-white devotion decks that try to abuse Ajani's Pridemate with plenty of lifegain triggers.
The aggro start can be pretty strong with turn 1 Healer's Hawk -> turn 2 Ajani's Pridemate -> turn 3 Linden, the Steadfast Queen or Heliod, Sun-Crowned - it's possible to take the kill by turn 4 or 5. Linden and Heliod can be really crazy together even without a Ajani's Pridemate. When you pump counters with Heliod, Sun-Crowned try to spread them evenly so you dont suffer too hard when your big creature gets removed.
Plan B for this deck is to stack enchantment ETB triggers on Archon of Sun's Grace so you can create flying lifelink army. It is slow but powerful - it's sweet when you play Alseid of Life's Bounty for one mana and you get a free pegasus token and two lifegain triggers from Daxos, Blessed by the Sun. However most of the time it's better to go for turn 4 Ajani, Strength of the Pride instead of Archon of Sun's Grace because this is your A plan and it's faster.
In case of a standoff this deck really shines - you are able to generate a lot of tokens and your Ajani's Pridemate and Heliod, Sun-Crowned triggers are making your dudes bigger than anything that most decks can come up with. The ultimate of the Ajani, Strength of the Pride is a good way to clear the board and finish the game and this is not just theoretical but actually happens.
I also run 2 x Dawn of Hope which helps in long games and allows you to keep up when you face off decks that are heavy on the removal side. Mono white devotion decks that do not run it are usually faster but they really crumble vs control and I hate that.
2 x Lurrus of the Dream-Den also helps alot - recasting Ajani's Pridemate or Daxos, Blessed by the Sun is pretty big deal but my favorite play is to just keep sacking Alseid of Life's Bounty for protection and replaying it with Lurrus. The lifelink on Lurrus also stacks well with the overall strategy.
2 x Angelic Gift - you really need the card draw, also flying can help your big Ajani's Pridemate to hit for lethal and the enchantment ETB trigger is nice.
Your main strategy is aggro so your starting hand matters alot and if it's not fast enough it's a good idea to mulligan.
