Hottest card at the moment - Lord Ariantus - What other cards are worth investing?

Buckethead is the hottest card at the moment, everyone is talking about it, everyone is buying it. Currently, Lord Ariantus is selling for $7.80 on the market, triple of what it used to be just a month ago.

The reason for this is due to a report released by foggybottom with data claiming that 90% of this card were released into circulation (LA has a total supply of 10000 cards only). This resulted in a frenzy buying among players. Lord Ariantus is a Legendary card, from the Rewards edition. This means that the only way to obtain this card is pulling from daily/season rewards, or buying from the market. So even people like j6969, who already opened thousands of packs, can only get this card from the market.

Another card that had surge in pricing over the weeks is Elven Cutthroat. Selling for $0.60 on the market now, and as high as 74c a couple of days ago.

So, are there any other cards worth investing in? I think a card needs to fit some criteria here

• Has a fixed/limited supply. There are only 10% Lord Ariantus left to be pulled. Supply is dropping and so price has to go up. Beta packs are selling out fast and there are rumours that Beta cards will not get printed. So the rarer cards like the Legendaries should see a price increase soon. Especially the Neutral Epic and Legendaries, since they don't exist in Alpha and has a much lower supply.
• Is widely used by all players. Lord Ariantus is undoubtedly the most used card in the higher leagues. A super tank and Neutral, useful in many ruleset. The introduction of Double Ruleset is benefitting the Life Splinter. We are seeing more "Broken Arrows", that makes Sneak one of the most utilised strategy (at least in the games that I played recently). Elven becomes the indispensable choice here. I believe this is the reason for her price surge in recent days. Going Neutral must be the right choice.
• Don't forget the lower leagues. Water Splinter is one of the most popular in lower leagues, but is terrible in Diamond/Champions. But prices for Water cards is among the highest! When Splinterlands mobile app is launch later in the year, I am sure we will see many more new players. These newcomers will be needing the Water Splinter most. And then, price goes up.

Considering all the above, here are a few cards that I see great potential in, and will try to buy some and hodl.

• Cocatrice
• Hydra
• Selenia Sky
• Spineback Turtle
• Crustacean King
• Electric Eels
• Serpentine Soldier
• Silvershield Paladin
• Gold Dragon
• Enchanted Defender (probably the most underrated card)
• All Gold Foils. These shiny cards are so so cheap now, most of them selling at the DEC value. I really hope the Splinterlands team will come out with more ways to make Gold cards playable. Can't we just have a separate ladder for Gold Foils card? Not that difficult to implement right? :)

What other cards do you think has great potential to invest in?