The One Ring provides complete protection from damage for a turn, then it gains a Burden counter at the cost of a life each turn after
Nuking a dual land and putting your opponent behind by a turn, while simultaneously putting yourself ahead by a turn (or four) seems devastating, especially if your curve continues well past 6 (which it ought to!) The question is not is this a good card, because the answer to that is, objectively, yes
Based on the latest market prices tracked on TCG Stacked, Pikachu is worth about $105.68 USD
Hop's Dubwool, however, appears to be a US-only promo for now, and there's no mention of where European Pokemon fans might be able to get the cards
While not among the most expensive cards, it is highly desired for its inclusion in a well-rounded OP-01 collection