The Miser is probably the most misunderstood card. Hopefully we can clear up any confusion about it!
This will give you some different strategies you can consider with the Miser as well as an example of how to play the ability.
When you obtain the Miser, your opportunity to gain booty increases significantly! The Miser's ability allows you to use any Belay type card as if it were a "2 Doubloons" card. That is, when it comes to your turn, if you want to, you can use a Belay card instead of playing a Loot card. This essentially allows you to add value to cards that would have otherwise been used on someone else. It also gives you more variety of how to play. You can be more strategic with your cards and either go for extra booty or thwart other players.
One strategy of the Miser is getting booty from the "Walk the Plank" card. With the Miser, instead of removing other crewmates, you can use "Walk the Plank" to earn booty for yourself! Not only does it reduce the risk of losing the Miser, it earns you booty in the process. This greatly increases your potential to gain big stacks of booty per round.
To do so, on your turn while you have control of the Miser, simply declare that you are using the Miser's ability and place the "Walk the Plank" card face up in front of you as if it where a Loot card. You can now earn two booty.
Another possibility is to grab the "Fool's Gold" cards. Now players will not be able to stop you and you can collect two booty per each one! This will force other players to use "Mutiny" to block Loot cards instead. We all know that Mutiny is best used to defend yourself from attacks or to counter another player. With no "Fool's Gold" cards around, the other players will have to block high booty rewarding cards like "Repeat" and "3 Doubloons" using their precious "Mutiny" cards. Shiver me timbers!
Be wary! Other players can block your Miser's cards with "Fool's Gold" or "Extortions!" Hopefully your hand contains all of the "Fool's Gold" cards so no one will be able to block you! This allows you to benefit greatly from the Miser's special ability.
As with all great things, there are some disadvantages.
Due to the nature of the ability, you may not skip your turn if you are holding any cards in your hand. This is due to the rule that you must play a Loot card on your turn. The Miser effectively turns all of your Belay cards into potential Loot cards, therefore, you have Loot cards to play on your turn.
Another downside to having the Miser... is losing him. If you grab only Belay cards with the plan to convert them to Loot cards, you might be stuck with no booty for the round if the Miser is removed! You must be strategic and balance risk with reward.
Do you take advantage of the ability and use only Belay cards?
Do you grab some Loot cards just in case the Miser takes a plunge into the depths?
Or do you grab extra "Mutiny" cards to defend the Miser till the end?
Ultimately the choice is up to you!
With the Miser on your side, there is no end to earning booty!