It's clear that Ajani's Mantra and Ajani's Pridemate interact synergystically with Ajani Goldmane himself. However, they don't interact all that well with very many other cards. Another problem is that Ajani Goldmane is at his best in White Weenie style decks, or token decks. The problem here is that while Ajani's Pridemate is fine for such a deck, his Mantra isn't a card that white weenie decks really want to run. It just dillutes the power of the deck, and only contributes in a measurable way if you also happen to draw the Pridemate.
Thus I was having trouble conceptualizing what kind of deck would want both Ajani's Mantra and Ajani's Pridemate. Then I remembered an old favorite of mine, a card that was just dying for a card like Ajani's Mantra to be printed...
I'd already put this card to good use before, but Ajani's Mantra is a far better companion to Searing Meditation than most of what I'd been using before. Obviously Firemane Angel was a sure thing, and I found a kindred spirit in Recumbent Bliss. So with these ideas in mind, I was off... this is what I came up with:
4 Ajani's Pridemate
3 Wall of Reverence
2 Cunning Sparkmage
2 Balefire Liege
4 Firemane Angel
4 Ajani's Mantra
4 Lightning Helix
4 Recumbent Bliss
4 Searing Meditation
3 Ajani Vengeant
2 Basilisk Collar
2 Sacred Foundary
3 Boros Garrison
2 Rugged Prairie
2 Battlefield Forge
1 Sunhome, Fortress of the Legion
Okay, so I mentioned breaking the rules a bit here, and you'll notice that I'm using Ajani Vengeant rather than Ajani Goldmane. Well, I feel that is an acceptable compromise. The problem is that this is the only deck I could really see Ajani's Mantra being good in, but it doesn't really run enough creatures to make Ajani Goldmane worth running. Besides, most of my Ajani Goldmanes are tied up in my mono-W Knight deck... fortunately Ajani Vengeant works just as well with his two signature spells, AND fits this style of deck much better than his original incarnation.
The 2 copies each of Shard Phoenix, Balefire Liege and Brightflame are all iffy at this point, but I like each of those cards, so I'll give 'em a chance. Anyway, there are obviously a whole slew of incremental lifegain effects here to power up your Meditations and Pridemates. You should have a 8/8 Pridemate swinging before long. Lighning Helix and Searing Meditaion will clear the way of little chump blockers and Recumbent Bliss takes care of anything your burn can't handle. Wall of Reverence and Shard Phoenix take on defensive duties, and help protect Ajani Vengeant.
Brigtflame and Firemane Angel are late game cards, and this is a deck that won't often win fast. It CAN, but it has to get just the right draw. Generally you're just going to want to play defensively and try to neutralize any significant threats while your Pridemates beef up. Once you feel you are stable, start swinging with Pridemates and Firemanes until your opponent is charred. Feel free to start sending Searing Meditation blasts at their dome too, once they run out of little guys to kill.
The tricky thing about this deck is that it ties up a LOT of mana, once you get Searing Meditation online. Often you will have to choose between activating the Meditation one, two or three times on your upkeep, or holding back some of that mana to play something from your hand. A good rule of thumb is to just activate Meditation unless you REALLY need to cast something. If you can survive without casting anything, then try to win with Searing Meditation advantage. That way, if your opponent manages to kill the Meditation later, you will have more stuff in hand to keep pressing the advantage anyway. Also, don't cast multiple Searing Meditations, unless your opponent is playing Red or Black (or both) because they can't kill Enchantments, but may make you discard them. Againts White or Green, though NEVER drop more than one at a time.
Well, that's about it, but I'll try to update this post if I make any changes to the decklist.
UPDATE: I borrowed a nifty little standard combo for this deck in the form of Cunning Sparkmage + Basilisk Collar. This has the advantage of letting me ping an opponent's creature to one-shot it (thanks to the Collar's Deathtouch ability) and gain 1 point of life as I do it, hopefully triggering a Searing Meditation in the process. It's not uber-powerful, but highly synergistic and fits into the deck very well. It's untested as of this post, but I already like it better than the unwieldy Brighflame and Shard Phoenix (both were just holdovers from an older version of this deck).