Retention has been the go-to statistic used to gauge quality of a game and a pretty reliable scale to calculate the lifetime of a game. Day 1,7,30,60,90 etc. retention numbers pretty much tell you how the game is going to perform in terms of revenue and growth and if that game is worth investing time and money on for future content.
But what about games that have been in the market for 5+ years? The games that are dominated by the ‘elder’ player base. Players who have been with the game and seen it go through all its ups and downs. How do we mix things up and keep the players in-game and interested? Fortunately I have had the opportunity to try something new for two very different games, both of which saw reasonable success (In terms of improvement of revenue and retention).
Example 1: A Time Management Game (RY:BB)
This was a typical time management game with a saga-map type level progression which had been live for about 2 years. The core loop involved grinding soft currency to upgrade appliances that help cook and serve desserts faster to earn soft currency.
This game had over 250 levels released when the player base started to dwindle, because of repetition of gameplay combined with little to no social activity. When it was time to release a new feature, the biggest priority was to improve retention first, followed by monetization. What could be done?

The Answer: Async PvP. When I say PvP, I do not mean in the traditional sense. Rather, we wanted to pitch the elder players against each other in a good ol’ fashioned leaderboard, that was unlike the typical saga map level leaderboard.
Instead a new ‘Land’ with 5 levels was added that had slightly different gameplay mechanics from the core loop, by removing the grind of the soft currency and focusing only on the high score which made it more skill based. Top it with attractive rewards for the best players and we got ourselves a pretty decent feature that helped extend the session length and also monetization by a little bit.

The feature was run as a limited time event, promising new power ups and hard currency as the top rewards. The feature monetized with tokens that were used to attempt the special land.
The players had quite the positive reaction to the feature. More engagement was seen from the elder players, who now got a platform to showcase their skills and an alternative way to earn hard currency and rare power-ups.
The feature was also designed in such a way that it could be auto-run and cycled with different challenge ‘objectives’ and rewards. Thus reducing production cost and effort.
Conclusion: By playing around the pre-set game rules and bringing in a new social element in an otherwise grindy arcade game, it could give the players a fresh new avenue to showcase their skills.
Example 2: A Midcore Base Building Game (RY:TGF)
The second example is a base building/fighting strategy game where a player expands their empire by raising an army and attacking other player bases to earn resources.
This game has been live for over 6 years, which is a pretty long time. Most of the player base consisted of elder players who have been playing for >5 years.

PvP was already an integral part of the core loop of the game in this case. However the in-game economy was still quite tight knit and there was a lot of rare items worth chasing, with not enough avenues to earn them. So the idea was to provide the players a break from the constant headbutting with each other, and instead offered them a chance to earn super rare and exclusive rewards from the game without the grind.
The Answer: A tier based boss battle, in which the player gets to fight 10 bosses back to back progressively in an all out slug fest. This would give them an opportunity to earn the rarest of the rare rewards whilst sinking all of their bloated troops from their inventory.

Players were delighted by this feature, especially after all the teasers and lore that went into releasing the feature. They were also given 5 free tries at the first 5 bosses, who were easiest, and hence guaranteed rewards.
The intention of this was to help the lower level players access the feature and farm items that would help them progress the game faster, this also improved retention of the lower level players. The elder players enjoyed the challenge and the rarer rewards of the higher tier bosses. Also additionally, we also had a leaderboard based on one of the game parameters and the top scorers were given even more rewards. The feature monetized with tokens that were used to attack each boss.
Conclusion: By analyzing the current state of the game economy, we were able to identify that the missing element the game was with the difficulty of reliably farming rare items in game, and the feature filled that void and managed to perform above and beyond by being accessible to the lower level/non paying players and equally challenging for an experienced elder.
Finally, the lesson that can be learned from all this is that, sometimes by utilizing the game mechanics in non-conventional ways (PvP in a PvE game and vice versa), we were able to inject new life to the games and the players themselves were able to enjoy the content since it was a breath of fresh air from the usual grind of the core loop. All in all, a win-win situation!